<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 18th August 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you poster by <strong>Agilent Technologies / ASMS </strong>and application note<strong> </strong>by<strong> Shimadzu!</strong></p><h3><strong>1. Agilent Technologies / ASMS: New Pollutant Screening of Environmental Samples Using High-Resolution GC/Q-TOF and Accurate Mass Spectral Library of Emerging Environmental Pollutants&nbsp;</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_7250_pdcl_library_pal3_suremass_asms_2025_thp_083_en_agilent_3f1ac53d50.pdf"><strong>Full PDF for download</strong></a></li></ul><p>This paper conducts qualitative and semi - quantitative analysis of complex GC/Q-TOF sample data by using high-resolution, accurate-mass gas chromatography/quadrupole time-of-flight mass spectrometry (GC/Q-TOF), an accurate mass spectral library of environmental pollutants specifically created for emerging pollutant screening, and analytical software with a screening process platform. Actual environmental water samples are used to verify the sensitivity, accuracy, and spiked recovery rate of the solution. All results confirm that this solution is simple, stable, and effective, providing technical support for emerging pollutant screening.</p><h4><strong>Experimental</strong></h4><h5><strong>Instrument Analysis&nbsp;</strong></h5><p>The samples were analyzed by <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC"><strong>Agilent 8890 GC</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7250+GC%2FQ-TOF"><strong>7250 high resolution accurate mass GC/Q-TOF system</strong></a>, It was configurated with a mid-column backflush setup (Figure 1). A 55.5 - min retention time locked GC oven temperature program is utilized which is listed in Table 1. The key mass spectrometry parameters of the GC/Q-TOF are as follows: It operates in the Electron Ionization (EI) mode with an energy of 70 electron volts, conducts detection in the time-of-flight scan mode within a mass-to-charge ratio range of 50 - 1000. The spectral acquisition rate is 5 Hz, and both the interface temperature and the source temperature are set at 280 °C. Data analysis is performed with the assistance of MassHunter data analysis software. The high-resolution accurate mass spectral library employed in the screening process is independently created by the laboratory.</p><h5><strong>Data Analysis&nbsp;</strong></h5><ul><li>The data processing used Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=Masshunter+software"><strong>Masshunter data analysis software</strong></a>, including Suremass.&nbsp;</li><li>The target screening of new pollutants was based on an independently created by the laboratory GC/Q-TOF PCDL library<sup>1</sup>.</li></ul><h4><strong>Conclusions&nbsp;</strong></h4><ul><li>Based on the currently collected list of new pollutants, a truly meaningful new pollutant PCDL high-resolution spectral library has been created.&nbsp;</li><li>This work demonstrated a total workflow for targeted screening and semi-quantification in real water sample.&nbsp;</li><li>The confidence in identification of new pollutants was enhanced by stable RT and excellent mass accuracy as a result of using an RTL backflush method and highresolution accurate mass measurement.</li></ul><h3><strong>2. Shimadzu: Analysis of SAF Using Comprehensive Two- Dimensional Gas Chromatography (GC× GC)&nbsp;</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00862_en_f1ee0a435f.pdf"><strong>Full PDF for download</strong></a></li></ul><h4><strong>User Benefits</strong></h4><ul><li>By comparing chromatograms obtained as two-dimensional images, it can be utilized for quality control Inspection of SAF.</li><li>Changing the column combination customizes separation characteristics to the sample composition.</li><li>Utilizing the FASST (Fast Automated Scan/SIM Type) allows for the simultaneous analysis of the composition of SAF and the quantitative analysis of antioxidants.</li></ul><p>SAF (Sustainable Aviation Fuel) produced from waste cooking oil, used paper, and sugarcane has gained attention in recent years from the perspective of achieving a carbon neutral society. The physical properties of SAF,such as combustibility, vary depending on its components. Therefore, component analysis of SAF is crucial; however, since SAF is a mixture of various hydrocarbons, complete separation of each component is extremely challenging. Comprehensive two-dimensional gas chromatography (GC×GC), which utilizes the separation characteristics of two different types of columns, is an effective method for analyzing SAF with such a complex composition. Additionally, the GCMS-QP2050 enables ultra-fast scanning (30,000 u/sec), which improves the separation of adjacent peaks and allows for high-precision qualitative analysis(Application News No.01-00788-EN).</p><p>In this application, two types of SAF (A and B) and one intermediate product from the SAF production process (C) were measured using a combination of GC×GC with a non-polar column as the first column and a medium-polarity column as the second column. The two-dimensional images allow for a visual representation of the composition distribution, making quality control Inspection. Moreover, high separation of paraffins and naphthenes using a combination of a medium-polar column as the first column and a non-polar column asthe second column, as well as the quantification of antioxidants in SAF, which are regulated by concentration in ASTM D2425 will be introduced.</p><h5><strong>System Configuration</strong></h5><ul><li><strong>GC Model</strong>: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis%E2%84%A2+GC-2030"><strong>Nexis GC-2030</strong></a> / <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-30i"><strong>AOC-30i</strong></a></li><li><strong>MS Model</strong>: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a> (TMP exhaust: 255 L/sec)</li><li><strong>Injection Port</strong>: SPL</li><li><strong>Modulator: </strong>ZX1 thermal modulator (ZOEX corp.)</li><li><strong>Nitrogen generator: </strong>MT-24F (System Instruments Co., Ltd.)</li><li><strong>Software</strong>:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Labsolutions+GCMS"><strong>Labsolutions<sup>TM</sup> GCMS</strong></a></li><li>GC Image (GC Image, LLC)</li></ul></li><li><strong>Library: </strong>NIST Mass Spectral Library</li></ul><h4><strong>Conclusion</strong></h4><p>Three SAF samples were measured using a combination of lowpolar to medium polar columns and compared the twodimensional images. The two-dimensional images allow for intuitive comprehension of the distribution of each component, making it easy to identify differences in composition and conducting quality control Inspection. Additionally, in the measurement of SAF using a combination of medium-polar to non-polar columns, the separation of paraffins and naphthenes was improved. Furthermore, by utilizing the FASST, composition analysis of SAF and quantitative analysis of antioxidants were simultaneously performed, which are regulated by concentration in ASTM D2425.</p>

News from LabRulezGCMS Library - Week 34, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 25th August 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you application notes by <strong>Agilent Technologies </strong>and <strong>Shimadzu!</strong></p><h3><strong>1. Agilent Technologies: A More Sustainable Analysis of Ethylene Oxide and 1,4-Dioxane</strong><br><strong>in Surfactants with Hydrogen Carrier Gas&nbsp;</strong></h3><p><strong>Using an Agilent </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977B+GC%2FMSD"><strong>5977B GC/MSD</strong></a><strong> with an Agilent HydroInert Source</strong></p><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_ethylene_oxide_1_4_dioxane_surfactants_hydrogen_carrier_gas_5994_8335en_agilent_886a988649.pdf"><strong>Full PDF for download</strong></a></li></ul><p>EO and 1,4-dioxane are key industrial chemicals, frequently found in the production of surfactants. During alkoxylation processes, residual raw materials or byproducts, such as EO and 1,4-dioxane, may remain in the final surfactant product (Figure 1). Although manufacturers have made significant strides in reducing these byproducts, increasing regulatory scrutiny on EO and 1,4-dioxane underscores the need for precise analytical methods to detect these compounds at low concentrations.1–4 Thus, there is an urgent need to develop methods that can accurately quantify these compounds at levels as low as 0.1 ppm in consumer products.</p><p>This study presents a method for the detection of EO and 1,4-dioxane using GC/MS with an HS sampler and a HydroInert source for hydrogen carrier gas. The use of hydrogen instead of helium not only addresses the global helium shortage but also ensures excellent sensitivity and linearity, while maintaining the integrity of the analytical process. The HydroInert source further eliminates chemical reactions often associated with hydrogen in mass spectrometry, offering a sustainable and reliable solution. The method developed in this study successfully quantifies both EO and 1,4-dioxane at the low concentrations required by current regulations, offering an accurate, reliable approach for compliance in surfactant manufacturing.</p><h4><strong>Experimental&nbsp;</strong></h4><p>This work was carried out using an Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7890+GC"><strong>7890 GC</strong></a> with helium carrier gas and an Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC"><strong>8890 GC</strong></a> with hydrogen carrier gas. Both GC systems were configured with an Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977B+GC%2FMSD"><strong>5977B GC/MSD</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=PAL3+autosampler"><strong>PAL3 autosampler</strong></a> for headspace sampling. For the analysis using hydrogen carrier gas, the GC/MSD was fitted with a HydroInert source. The HydroInert source produces spectra in hydrogen that closely match those from helium-based libraries, such as NIST. This ensures spectral fidelity, allowing the same quantification and qualifier ions used in helium methods to be applied in SIM and MRM modes with hydrogen. Method parameters are shown in Table 1.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>This work establishes a first of its kind method using hydrogen carrier gas to reliably measure ethylene oxide and 1,4-dioxane in surfactants. Mass spectrometry detection was optimized for use with hydrogen by installing an Agilent HydroInert source. The HydroInert source helps to avoid sensitivity loss and spectral anomalies that are common with hydrogen carrier gas applications, resulting in suitable linearity, precision, accuracy, and LOQs for this analysis.</p><h3><strong>2. Shimadzu: How Long Does A Perfume Last on Skin? – Fragrance Analysis by </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a><strong> and Smart Aroma Database</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_04_ad_0309_en_60c887beed.pdf"><strong>Full PDF for download</strong></a></li></ul><h4><strong>User Benefits</strong></h4><ul><li>Achieve highly accurate and reproducible analysis of aroma compounds on human skin, ensuring reliable data for evaluating perfume performance.</li><li>Smart Aroma Database simplifies the qualitative and quantitative analysis process, reducing the time and effort required for data interpretation.</li></ul><p>The duration on how long fragrance lasts on human skin is a critical factor in the development and evaluation of perfumes. Gas Chromatography Mass Spectrometry (GC-MS) is a powerful analytical technique that allows for the detailed analysis of volatile and semi-volatile compounds, making it an ideal tool for studying fragrance. In this application note, a study was performed to examine fragrance on human skin at different durations after applying a perfume. Here, we explore the use of a Monolithic Material Sorptive Extraction (MMSE) MonoTrap, a sorptive extraction device to extract fragrance from human skin, followed by analysis using Shimadzu GCMS-QP2050 (Fig.1). Additionally, Smart Aroma Database was used to simplify the method development.</p><h4><strong>Experimental</strong></h4><h5><strong>Instrumental and Analytical Conditions&nbsp;</strong></h5><p><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a> (Shimadzu Corporation, Japan) was employed in this work (Fig. 1). The details of the system configuration is shown in Table 1. Sample acquisition was done by following the analytical method from Shimadzu <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Smart+Aroma+Database"><strong>Smart Aroma Database</strong></a>. MonoTrap SG DCC18 was purchased from GL Sciences, Japan (catalog no. 1050-70002).</p><h4><strong>Results &amp; Discussion&nbsp;</strong></h4><h5><strong>Fragrance Compounds Detection&nbsp;</strong></h5><p>The scan total ion chromatogram (TIC) of the diluted perfume sample is shown in Fig. 4. A total of 60 out of the 498 fragrance compounds in Smart Aroma Database were detected. These compounds were then monitored for this study. Fig. 5 shows a few mass chromatograms of the monitored fragrance compounds.</p><h5><strong>On-skin Fragrance Study&nbsp;</strong></h5><p>The on-skin fragrance study was conducted to evaluate the persistence of perfume compounds over time. Sampling was performed at three distinct time points: 15 minutes, 1 hour, and 6 hours after applying the perfume (as described in Fig. 2). Fig. 6 shows the percentage of compounds detected (out of 60 compounds) in these three different time points.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>In this study, we demonstrate the effectiveness of using GCMSQP2050 with Smart Aroma Database and Monotrap adsorbent to analyze the behavior of perfume fragrance on human skin. The result shows decrease percentage of number of compounds detected over time. The peak area of most compounds were reduced as well. Sampling repeatability shows that 57 out of 58 detected aroma compounds exhibiting %RSD values below 20% (n=3).</p>

News from LabRulezGCMS Library - Week 35, 2025

<p><strong>This study investigates peach ripening using Fourier transform near-infrared spectroscopy and volatilome-based headspace gas chromatography coupled to ion mobility spectrometry and mass spectrometry. A total of 344 samples from two varieties at different ripening stages were analyzed to identify optimal harvest timing.</strong></p><p>Principal component analysis revealed distinct clustering of samples by ripening stage. Using these groups, partial least-squares discriminant analysis models successfully differentiated both ripening stages and varieties. The results demonstrate strong potential for volatilome profiling with HS-GC–IMS and HS-GC–MS as reliable tools for monitoring peach quality.</p><blockquote><h4><strong>The original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.jafc.5c01524"><strong>Fingerprinting of Peach During the Ripening Process Using an Analytical Platform with Spectrometric and Volatilome-Based Chromatographic Techniques</strong></a></h4><p>Claudia Giménez-Campillo, Natalia Arroyo-Manzanares, Marta Pastor-Belda, Natalia Campillo, Lukas Bodenbender, Philipp Weller, and Pilar Viñas*</p><p>J. Agric. Food Chem. 2025, 73, 26, 16636–16647</p><p><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acs.jafc.5c01524">https://doi.org/10.1021/acs.jafc.5c01524</a></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><p><strong>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.</strong></p><p>Peach, along with nectarine, plum, apricot, cherry, and almond, belongs to the genus <i>Prunus</i> (genus described by Charles Linnaeus in 1753). <a href="javascript:void(0);">(1)</a> Originally from China, it is the second most important fruit in Europe after apple, <a href="javascript:void(0);">(2)</a> is of great economic importance, and is consumed fresh, canned and in juice. It is rich in vitamins, minerals, and antioxidants. Currently, in addition to China, there are other world leaders in the production of this fruit, including Spain, Italy, Turkey, and Greece. <a href="javascript:void(0);">(3)</a></p><p>In recent decades, consumer complaints about poor fruit quality have often been the result of premature harvesting for commercial reasons. This practice, while facilitating transport and distribution by extending the fruit’s presence in the market, has a negative impact on its flavor, texture, and nutritional value. Consequently, ripening monitoring and control have become an important part of fruit management. <a href="javascript:void(0);">(4)</a> Despite extensive research on the physicochemical properties of peaches during the ripening stage to obtain adequate maturity indices, objective indicators of consumer acceptance are still lacking. <a href="javascript:void(0);">(5)</a> Ripening time has been shown to be directly related to flavor characteristics, which are influenced by sugar accumulation, acidity, and the production of low-molecular-weight volatile organic compounds (VOCs), <a href="javascript:void(0);">(6)</a> also called volatilomes. Therefore, VOCs can be a key indicator in peach quality assessment. Understanding exactly which VOCs are responsible for aroma at different ripening stages can help to develop rational and objective methods to ensure high-quality fruit, both in consumption and processing. <a href="javascript:void(0);">(7)</a> This approach would not only be beneficial for consumers, who would receive products with optimal flavor, texture, and nutritional value, but also would support producers.</p><p>A literature review reveals the existence of several studies on the characteristic volatile profile of peaches. <a href="javascript:void(0);">(1,8−14)</a> However, it is important to note that there is a significant lack of research on the variation of these compounds during ripening. <a href="javascript:void(0);">(15)</a> Most of the works on VOC determination used gas chromatography coupled to mass spectrometry (GC–MS) <a href="javascript:void(0);">(1,6,8−19)</a> and solid-phase microextraction as the sample preparation technique. <a href="javascript:void(0);">(6,9−12,15−17,19)</a> In recent years, ion mobility spectrometry (IMS) has been used as an alternative technique for the determination of VOCs in peach. <a href="javascript:void(0);">(11,12,18,20,21)</a> The aim of these studies was to investigate the volatile profile, <a href="javascript:void(0);">(11)</a> the differentiation between varieties, <a href="javascript:void(0);">(18)</a> and the influence of packaging and storage of this fruit. <a href="javascript:void(0);">(20,21)</a> Therefore, the current state-of-the art techniques reveal that GC–MS and GC–IMS techniques have not been applied to predict peach ripening. It has been shown that it is possible to predict optimal ripening by near-infrared spectrometry (NIR) in relation to the measurement of different parameters, such as soluble solid content, <a href="javascript:void(0);">(22−28)</a> flesh firmness, <a href="javascript:void(0);">(23,26,28,29)</a> pectin content, <a href="javascript:void(0);">(30)</a> dry matter, <a href="javascript:void(0);">(23−25)</a> absorbance difference index, <a href="javascript:void(0);">(25,26)</a> and acidity. <a href="javascript:void(0);">(27)</a></p><p>The objective of this work was the development of methodologies for the prediction of the ripening stage of peaches and, therefore, of their quality for the consumer by means of a simple analysis based on their VOC content, applying headspace GC (HS-GC)–MS and HS-GC–IMS techniques and on their Fourier transform near-infrared spectroscopy (FT-NIR) spectral fingerprint. The novelty of the study lies in the fact that correlations have not been established with other chemical parameters measured in peaches, but rather chemometric models based on an analytical platform have been applied to obtain relevant information on the ripening of this fruit. The studies were conducted on two different peach varieties (yellow-fleshed and red-fleshed) grown in one geographical origin of the agricultural sector (Jumilla, Region of Murcia, Spain), which have not been previously analyzed, and chemometric models were also applied to discriminate between these two varieties.</p><h4><strong>2. Materials and Methods</strong></h4><h5><strong>2.2. Instruments, Analytical Procedures, and Data Processing</strong></h5><h5><strong>2.2.1. FT-NIR Analysis</strong></h5><p>FT-NIR analysis was performed using a FT-NIR multipurpose analyzer spectrophotometer, equipped with a solid sample compartment, from Bruker Optik GmbH (Ettlingen, Germany).</p><p>A weight of 0.5 g of homogenized peach was placed in a vial and measured by FT-NIR in the reflectance mode. Before each analysis, a background scan was performed, and the measurement was repeated five times. Spectral data covered the wavenumber range from 12,500 to 3600 cm<sup>–1</sup> with a resolution of 8 cm<sup>–1</sup> and are expressed in units of absorbance. Each spectrum was obtained from 32 scans, and the average of the five measurements for each peach sample was calculated to obtain a representative spectrum.</p><p>The FT-NIR software used to process the data was OPUS software, version 8.5. In addition, the data set obtained was subjected to three transformations using Unscrambler X software. Multiplicative scattering correction was applied to correct for the effects of particle-size-induced light scattering effects. Next, Savitzky–Golay smoothing was applied (window = 9, polyorder 2, first derivative) to reduce the inherent instrumental noise and to correct for the additive and multiplicative effects present in the spectrum. The full spectrum (2224 features) was used as a variable in the chemometric models constructed from the FT-NIR data. This approach was adopted in order to make use of all available spectral information given the observed variations between the samples across the entire range studied.</p><h5><strong>2.2.2. HS-GC–IMS Analysis</strong></h5><p>For GC-IMS analysis, a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=6890N"><strong>6890N gas chromatograph</strong></a> (version N.05.05) from Agilent Technologies (Waldbronn, Germany) was coupled to a G.A.S. (Gesellschaft für Analytische Sensorsysteme) IMS module (Dortmund, Germany). A <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=2&amp;search=multipurpose+sampler"><strong>multipurpose sampler</strong></a> (MPS) from Gerstel GmbH (Mühlheim, Germany) was used, configured for headspace mode and injecting the sample in the gas phase, using a 2.5 mL syringe. The carrier gas was nitrogen with a purity of 99.99%, operated at a constant flow rate of 1 mL min<sup>–1</sup>, and supplied by Air Liquide (Madrid, Spain). An Agilent HP-5MS UI capillary column (0.25 mm × 30 m with a film thickness of 0.25 μm), consisting of 5% diphenyl and 95% dimethyl polysiloxane, was used for the analysis.</p><h5><strong>2.2.3. HS-GC–MS Analysis</strong></h5><p>GC–MS analysis was carried out on an Agilent Technologies (Santa Clara, CA, USA) model <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+gas+chromatograph"><strong>8890 gas chromatograph</strong></a> and an Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977B"><strong>5977B quadrupole mass spectrometer</strong></a> equipped with an inert ion source. A <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=2&amp;search=multipurpose+sampler"><strong>Gerstel MPS</strong></a> operating in headspace mode was used for sample injection.</p><h4><strong>3. Results and Discussion</strong></h4><h5><strong>3.2. Spectral Peach Fingerprint Using FT-NIR</strong></h5><p>The spectral fingerprints of the peaches analyzed showed very similar profiles, with differences in the absorbance values. <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.jafc.5c01524#fig1">Figure 1</a> shows the FT-NIR spectra of the average raw data obtained from all peach samples collected at different stages of ripeness, recorded in the range 12,500–3600 cm<sup>–1</sup>. It is observed that as the ripening stage progresses, the absorbance increases in the range 11,800–3600 cm<sup>–1</sup>.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/J_Agric_Food_Chem_2025_73_26_16636_16647_Figure_1_Raw_FT_NIR_spectra_of_the_average_of_all_peach_samples_at_different_stages_of_ripening_T_b6e18989f1.jpg" alt="J. Agric. Food Chem. 2025, 73, 26, 16636–16647: Figure 1. Raw FT-NIR spectra of the average of all peach samples at different stages of ripening. The figure shows the FT-NIR spectra corresponding to the average of peach samples at different stages of ripeness: the blue spectrum represents unripe peaches, the red spectrum also represents unripe peaches but in a more advance ripeness process, and the green spectrum represents ripe peaches ready for consumption. Also, the most representative absorption bands of the peach observed in the spectra are indicated." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_J_Agric_Food_Chem_2025_73_26_16636_16647_Figure_1_Raw_FT_NIR_spectra_of_the_average_of_all_peach_samples_at_different_stages_of_ripening_T_b6e18989f1.jpg 245w," sizes="100vw" width="1600" height="857"></p><p>In the spectrum of the different peach samples, four different regions can be identified according to the NIR bands: 12,500–9400 cm<sup>–1</sup>, 9400–7700 cm<sup>–1</sup>, 7700–5800 cm<sup>–1</sup>, and 5800–3600 cm<sup>–1</sup>. Peach samples contain mainly water (85–95%) in their composition, and therefore characteristic water bands were found from right to left, including bands with different absorbances. In the first region, from 5800 to 3600 cm<sup>–1</sup>, there is a broad absorption band with a maximum at around 5160 cm<sup>–1</sup>, which corresponds to the first combination of asymmetric stretching and bending of the water molecule. Also, in this region, there is another narrow and weaker combination band at 5620 cm<sup>–1</sup>, associated with the bending, asymmetric stretching, and intramolecular modes of the water molecule. In the region between 7700 and 5800 cm<sup>–1</sup>, a broad band is observed at 6880 cm<sup>–1</sup> involving the symmetric and asymmetric stretching modes of the water molecule, known as the first overtone of OH stretching. Between 9400 and 7700 cm<sup>–1</sup>, there is a second weak combination band involving the symmetric stretching, asymmetric stretching, and bending modes of the water molecule. Finally, in the region from 12,500 to 9400 cm<sup>–1</sup>, an absorption band related to the asymmetric and symmetric stretching modes of the water molecule is observed, called the second overtone of OH stretching. <a href="javascript:void(0);">(35)</a> The spectra show that the maximum absorbance value of each band increases as the ripening stage progresses. This correlation suggests that the ripening process in peaches is associated with an increase in water content, which affects the texture, weight, and possibly the flavor of the fruit.</p><h5><strong>3.3. Identification and Quantification of Volatile Compounds Using GC–MS and GC–IMS</strong></h5><p>The volatile fingerprint of the peach samples was established by using GC coupled to MS and IMS detectors. <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.jafc.5c01524#fig2">Figures 2</a> and <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.jafc.5c01524#fig3">3</a> show a topographical map using IMS and a chromatogram obtained by the MS detector for a peach sample, respectively. In both cases, identification of the VOCs was carried out.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/J_Agric_Food_Chem_2025_73_26_16636_16647_Figure_2_Topographic_map_of_a_peach_sample_264e0b037c.jpg" alt="J. Agric. Food Chem. 2025, 73, 26, 16636–16647: Figure 2. Topographic map of a peach sample. The figure shows a topographical map obtained by HS-GC–IMS, indicating the VOCs identified and verified in peach samples." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_J_Agric_Food_Chem_2025_73_26_16636_16647_Figure_2_Topographic_map_of_a_peach_sample_264e0b037c.jpg 214w," sizes="100vw" width="996" height="726"></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/JAGRIC_3_28c1356481.jpg" alt="J. Agric. Food Chem. 2025, 73, 26, 16636–16647: Figure 3. Chromatogram of a peach sample. The figure shows a chromatogram obtained by HS-GC–MS, indicating the compounds identified and verified in peach samples." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_JAGRIC_3_28c1356481.jpg 212w," sizes="100vw" width="1600" height="1182"></p><p>Untargeted studies were performed by processing the raw data from the HS-GC–MS analysis of the samples using MS-DIAL software under the conditions described in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.jafc.5c01524#sec2_2_3">Section 2.2.3</a>. A total of 427 features were extracted from the peach samples, taking into account the different varieties and the whole ripening process.</p><p>HS-GC–IMS was used to obtain the topographical maps of all samples. The GC–MS metabolomic MSP spectral library and the GAS IMS library allowed putative identification of some of the features detected.</p><h4><strong>Conclusion</strong></h4><p>The results obtained allow us to conclude that both the quality and the specific variety of the peach can be verified by a single analysis of the volatilome or the NIR spectral fingerprint. However, better results are obtained in both cases when working with the volatile profile, since HS-GC–MS and HS-GC–IMS techniques are more powerful and specific tools. Although HS-GC–MS stands out for its high resolution and sensitivity, its high cost, the need for vacuum conditions, and the large size of the equipment limit its applicability in sectors with limited resources such as many fruit quality control companies. In contrast, the HS-GC–IMS technique offers greater simplicity, accessibility, and cost-effectiveness, as it requires less energy and resources, making it a more efficient and sustainable option. <a href="javascript:void(0);">(40)</a> Furthermore, its ability to provide results comparable to those of HS-GC–MS, as demonstrated in this work, underscores its potential as an ideal alternative for many studies seeking to reduce resource consumption without compromising analytical quality. <a href="javascript:void(0);">(41)</a></p><p>In summary, multiple factors must be considered to determine the best analytical tool for carrying out routine controls aimed at verifying the authenticity of labeling and predicting the optimal stage of ripening in order to prevent food fraud and minimize economic losses. These factors include economic cost, analysis time, complexity of sample preparation, and discrimination capability of the generated models. Although the FT-NIR technique allows for fast and relatively low-cost analysis, its analytical performance is significantly low. In some cases, the classification and validation percentages are close to 70%. HS-GC–MS, on the other hand, has shown very good discrimination capacity (with values above 87%), but it is limited by its high operating cost and greater instrumental complexity. Considering all these aspects, the technique that offers the most balanced approach for implementation in routine controls is HS-GC–IMS, as it combines excellent discrimination capability (with classification and validation percentages above 90% in all cases studied) with moderate analysis times, very simple sample preparation, and not very high operating costs. These features make HS-GC–IMS a particularly suitable tool for practical applications requiring a high degree of reliability, efficiency, and sustainability.</p><p>Although the results obtained were very promising, particularly regarding the volatile profiles analyzed by HS-GC–IMS and HS-GC–MS, the study has some limitations. First, the study focused on two peach varieties grown in a specific geographical region, so the applicability of the developed models to other varieties or geographical origin requires additional validation. Furthermore, while the chromatographic techniques used were successful, they call for specialized equipment, which might restrict their use in some situations. Future research should consider expanding the number of varieties and geographical origins.</p>

Fingerprinting of Peach During the Ripening Process Using an Analytical Platform with Spectrometric and Volatilome-Based Chromatographic Techniques

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 1st September 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you poster by <strong>Agilent Technologies / ASMS </strong>and application notes by <strong>EST Analytical</strong> and <strong>Shimadzu!</strong></p><h3><strong>1. Agilent Technologies / ASMS: Analysis of Phthalates Using GC/MS With Hydrogen Carrier Gas: The Importance of Reducing Interferences and Contamination&nbsp;</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_5977c_phthalates_hydrogen_gas_asms_2025_mp_359_en_agilent_d51f599179.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Due to the price of helium (He), many laboratories are looking for alternative carrier gases for their gas chromatography/mass spectrometry (GC/MS) methods. This work describes the evaluation of a single quadrupole GC/MS method for the analysis of 19 phthalates using hydrogen carrier gas and an EI source 1 . The method provides excellent peak shape, resolution, sensitivity, and a 13 min run time. Calibration curves were linear for 16 of the phthalates, with the remaining 3 alkoxy phthalates requiring a quadratic fit. Except for DINP and DIDP (mixtures of isomers), all compounds could be quantitated at low pg levels. Specific attention to the consumables used and their preparation before use is discussed and is important for reaching the lowest calibration levels.</p><h4><strong>Experimental</strong></h4><ul><li><strong>GC: </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+gc"><strong>Agilent 8890 GC</strong></a> with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7693A"><strong>Agilent 7693A automatic liquid sampler</strong></a> and tray</li><li><strong>Column: </strong>Agilent HP-5MS UI 20 m x 0.18 mm id x 0.18 µm (p/n 19091S-577UI)</li><li><strong>MSD: </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977C+GC%2FMSD"><strong>Agilent 5977C Inert Plus GC/MSD</strong></a></li></ul><h4><strong>Conclusions</strong></h4><ul><li>The Agilent 5977C GC/MSD and 8890 GC, when used with the method described here, provide excellent peak shape, resolution, sensitivity, and a 13 min run time..&nbsp;</li><li>The combination of hydrogen carrier and the Agilent J&amp;W HP-5ms 180 µm diameter column allowed for reduced analysis time relative to helium and a 250 µm diameter column .&nbsp;</li><li>Calibration curves were linear for 14 of the phthalates from 1 to 1,000 pg. DMEP and DBEP required quadratic curve fits, and DMEP and DEHP were calibrated from 2.5 to 1,000 pg. DINP and DIDP were calibrated from 50 to 20,000 pg with a linear fit.&nbsp;</li><li>Specific attention to the consumables used and their preparation before use is important for reaching the lowest calibration levels.</li></ul><h3><strong>2. EST Analytical: The Determination of Flavors in E-Liquids Using Purge and Trap Concentration</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_E_Liquid_Compound_Sampling_Using_Purge_and_Trap_5c709b52f0.pdf"><strong>Full PDF for download</strong></a></li></ul><p>E-liquid can be composed of propylene glycol or vegetable glycerin alone or can be a combination of the two. Propylene glycol is less viscous and carries better flavor. It also acts as a preservative. However, it does produce less vapor and some people are allergic to it. Vegetable glycerin, on the other hand, is much denser, is super hypoallergenic and produces more vapor. The drawback to the vegetable glycerin is that it is not a preservative, so the vape liquid will not last as long. Both glycerin and propylene glycol readily dissolve in water, so preparing the samples to test by purge and trap was relatively easy. Conversely, as the E-liquid emitted a strong odor of the added flavors, only a small amount of the solution could be used for analysis. The volatile flavor components of the vape liquid were examined by dissolving the solution in water and sampling the water using purge and trap.</p><h4><strong>Experimental</strong></h4><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>Evolution purge and trap concentrator </strong></a>was configured with a Vocarb 3000 trap. The trap was conditioned at 260ºC for one hour. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS syringe autosampler</strong></a> was set in water mode in order to run 5 ml samples. Next, samples were prepared using 10ul of vape solution dissolved in 100mls of de-ionized water. The parameters for the autosampler/purge and trap concentrator and the Gas Chromatograph/Mass Spectrometer (GC/MS) are outlined in Tables 1 and 2.</p><h4><strong>Conclusions</strong></h4><p>Since vape solution readily dissolves into water, purge and trap sampling proved to be an excellent technique for the determination of the volatile compounds in the E-liquids. Purge and trap sampling is an exhaustive sampling technique, so the results were very reproducible and provided the sensitivity to determine the lower level compounds in the solution. Furthermore, it was found that nicotine addition to the solution has an effect some of the compounds in the solution. So, the taste of the vape liquid is affected by the amount nicotine in the mix.</p><h3><strong>3. Shimadzu: Determination of Nitrobenzene Compounds in Nifedipine by GCMS&nbsp;</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_03_gcms_589_en_23eda751e7.pdf"><strong>Full PDF for download</strong></a></li></ul><h4><strong>User Benefits</strong></h4><ul><li>The direct dissolution protocol without pre-treatment, significantly enhancing analytical efficiency.</li><li>The specificity of the method is ensured by monitoring the characteristic ions of nitrobenzene compounds in selected ion monitoring (SIM) mode, which provides robust resistance to interferences.</li></ul><p>Nifedipine, a dihydropyridine calcium channel blocker with vasodilatory properties, is primarily indicated for the clinical management of hypertension and angina pectoris. Its synthetic route commences with 2-nitrotoluene as the starting material. Notably, the intermediate 2-nitrobenzyl alcohol, the byproduct 2- nitrobenzyl bromide, the reaction product 2-nitrobenzaldehyde, and potential impurities (3-nitrobenzaldehyde and 4- nitrobenzaldehyde) all contain nitrobenzene moieties, rendering them candidatesfor monitoring as potential genotoxic impurities. Previous studies have demonstrated that 2-nitrobenzaldehyde and 4-nitrobenzaldehyde exhibit mutagenicity in the Ames test, while 2-nitrotoluene has shown carcinogenicity in animal experiments. In accordance with the toxicological concern threshold (TTC) control approach specified in ICH M7, a threshold of 1.5 μg/day is recommended for genotoxic impurities in pharmaceuticals intended for lifelong administration. In this study, a method for the determination of six genotoxic impurities in nifedipine was developed using a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>Shimadzu GCMSQP2050</strong></a> gas chromatography mass spectrometry. This method features simplified sample preparation, high sensitivity, and favorable repeatability, thereby enabling effective monitoring of the six nitrobenzene compounds as genotoxic impurities in nifedipine pharmaceutical.</p><h4><strong>Analytical Conditions</strong></h4><p>The analytical conditions are shown in Table1. <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a> system was used for this Application News.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>A GC-MS method was established for the quantification of six nitrobenzene genotoxic impurities in nifedipine pharmaceuticals using a Shimadzu GCMS-QP2050 system. The calibration curves showed excellent linearity within the concentration range of 20-200 μg/L, with correlation coefficients (R&gt;0.999). Precision was evaluated through six replicate injections of the 50 μg/L standard solution, and the relative standard deviations (RSDs) of peak areas for all analytes were less than 4%. Spike recovery experiments were performed at three concentration levels (0.005, 0.01, and 0.032 μg/g) in actual matrices, resulting in recovery rates ranging from 95.85% to 117.64%. This method is characterized by simplified sample preparation, high sensitivity (IDLs of 0.263-0.496 μg/L), and good repeatability. Overall, it provides a validated analytical strategy for quality control monitoring of the target genotoxic impurities.</p>

News from LabRulezGCMS Library - Week 36, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 15th September 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you posters by <strong>Agilent Technologies / ASMS, Shimadzu / ASMS </strong>and application note by <strong>EST Analytical!</strong></p><h3><strong>1. Agilent Technologies / ASMS: Beyond Aligners: Unmasking Hidden Extractables and Leachables in Orthodontic Devices</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_7250_extractables_leachables_asms_2025_tp_318_en_ucsf_3e88cfbf5c.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Increasingly popular in orthodontics, clear aligners promised to users’ improved comfort, compliance and flexibility. It also came with prolonged intraoral exposure. The literature on the potential for leaching components of the polymer used to manufacture the invisible aligners is sparse. Despite the benefits, user submitted cases in the FDA retrospective analysis report several adverse effect ranging from swelling, hives, itchiness and even difficulty breathing1 . Previous works examined the potential of leaching in retainers but used conditions far from the in-vivo setting2 . We used samples closest to user conditions and harnessed the power of Gas Chromatography High Resolution Mass Spectrometry (GC-HRMS) and the power of curated and annotated libraries to find candidate compounds that could be at the origin of the reported adverse effects. We also used multivariate statistics to establish relationships between the compounds and metadata.</p><h4><strong>Experimental</strong></h4><h5><strong>Sample Analysis&nbsp;</strong></h5><p>Samples were analyzed using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7250"><strong>Agilent 7250 accurate mass GC-qTOF</strong></a> equipped with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC"><strong>8890 GC</strong></a> and a DB-5MS UI column (30m x 0.25 x 0.25). The inlet temperature was 280°C and the transfer line temperature was 325°C. The oven program was as follows: 50°C for 1 min, ramp at 25°C to 170°C, hold for 1 min; then ramp at 15°C to 300°C, hold for 10 min; then ramp at 20 °C to 325°C and hold for 5 min. The solvent delay was 4 min. The data were acquired in electron ionization (EI) mode using mass range 45 to 1000 m/z. The source temperature was 230°C, and the emission current was 5 µA. A mix of alkanes was run along with the samples and blanks and an Extractables and Leachables (E&amp;L) standard mixture was run as a quality check.&nbsp;</p><h5><strong>Data Analysis&nbsp;</strong></h5><p>Retention indices were used in consolidating library matches in both the Agilent HRMS E&amp;L library and the NIST23 library. Data analysis was conducted on Unknown Analysis software from Agilent that performs compound annotation based on library matching and retention index. All compounds were individually reviewed based on ExactMass, retention index delta and library match factor (Figure 2). Canonical Correlation Analysis was performed using the FactoMineR package in R.</p><h4><strong>Conclusions</strong></h4><p>The aligners used in the current study were approved in the late 90s when E&amp;Ls methods were not as prominent or sensitive as they are today. This study stands out with:&nbsp;</p><ul><li>The first report of numerous E&amp;L compounds with known potential adverse effects in a population of clear aligner users&nbsp;</li><li>Providing an insight of the relationships between E&amp;Ls and user’s metadata such as age, DWT and TSS&nbsp;</li><li>Providing the necessary libraries to find parent compounds and their potential metabolites</li></ul><h3><strong>2. EST Analytical: Optimization of 1,4-Dioxane and Ethanol Detection Using USEPA Method 8260</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_1_4_Dioxane_and_Ethanol_by_8260_App_Note_b669c79f53.pdf"><strong>Full PDF for download</strong></a></li></ul><p>During the manufacture of pharmaceuticals, 1, 4-Dioxane is used as a cleansing agent. It is also a byproduct of plastic manufacturing. The most likely exposure to 1, 4-Dioxane is at an industrial site. However, if any 1, 4-Dioxane is released into the environment during manufacturing there is a potential for it to migrate into ground water. The fact that 1, 4-Dioxane is so miscible in water makes degradation of the chemical challenging. Ethanol, on the other hand, has been a popular gasoline additive. Since it burns more quickly and completely than gasoline, emissions from car exhaust are decreased. The downside of this is underground storage tank leakage and fuel spills cause ground water and drinking water to be contaminated with both the fuel and the ethanol additive. Since ethanol is also very miscible in water, the detection of ethanol contamination in water can be difficult.&nbsp;</p><p>There have been several innovations that help overcome the obstacles of detecting 1, 4-Dioxane and Ethanol. The first one is the SIM mode of the mass spectrometer. This mode allows better detection of hard to extract compounds. Furthermore, mass spectrometers are now equipped to run SIM/Scan, this not only helps detect more difficult compounds, but also enables the detection of an extensive list of USEPA Method 8260 compounds without having to run the samples twice. Advancements in purge and trap sampling have also facilitated better detection of these compounds. Most effective in this has been the ability to heat the samples. However, there are drawbacks to better detection. The most problematic of these is the tendency of 1, 4-Dioxane and Ethanol to “stick” to the glass ware. This susceptibility has caused many headaches in environmental labs.&nbsp;</p><p>This application note will investigate seven variations of purge and trap sampling. The data will then be evaluated in order to recommend the optimum purge and trap sampling parameters for your lab.</p><h4><strong>Experimental</strong></h4><p>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>EST Analytical Evolution concentrator</strong></a> affixed with a Vocarb 3000 trap. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS autosampler</strong></a> equipped with the syringe option was employed as the autosampler. The separation and analysis were performed by an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890A"><strong>Agilent 7890A Gas Chromatograph (GC)</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C"><strong>5975C inert XL Mass Spectrometer (MS)</strong></a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=9&amp;search=Rxi-624+Sil+MS"><strong>Restek Rxi-624 Sil MS</strong></a> 30m x 0.25mm x 1.4µm column. The purge and trap parameters used for this study are listed in Tables 1 and 2 while Table 3 shows the GC/MS parameters.</p><h4><strong>Conclusions</strong></h4><p>All seven purge and trap parameter iterations passed the USEPA Method 8260 requirements for linearity and method detection limits. The problem with some of the experimental parameters was found in the carryover and precision and accuracy studies. The carryover using the traditional sparge vessel showed a large amount of carryover for the Ethanol and 1, 4-Dioxane. Since the carryover was so high, the precision and accuracy data suffered. The Fritless/Bulbless sparge vessel, on the other hand, displayed much lower carryover for the Ethanol and 1, 4-Dioxane especially when the patented sparge bake was not used. However, the 1, 2, 4-Trichlorobenzene, Naphthalene and 1, 2, 3-Trichlorobenzene carryover after the 50ppb standard was above the lower limit of the curve. Thus, the sparge bake would be recommended in order to limit the carryover of the heavier compounds. The optimum purge and trap parameters proved to be the patented water extraction technique. This technique provided linearity and method detection limits that met the USEPA Method 8260 requirements, while providing excellent precision and accuracy data. During water extraction, the sample is transferred to an empty 40ml vial and then purged in the soil station of the Centurion. The “fresh” vial provides a clean sparge vessel for every sample thus limiting carryover for both the Ethanol and 1, 4-Dioxane and for the heavy compounds. This lack of carryover aided in providing optimum precision and accuracy and carryover results and would be the recommended method for examining these troublesome compounds.</p><h3><strong>3. Shimadzu / ASMS: Quantitation of Acetaldehyde, Ethylene Oxide, 2-Chloroethanol, Ethylene Glycol, 1,4-Dioxane &amp; Diethylene Glycol in PEG 3350 by using dynamic headspace GC-MS/MS</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ASMS_2025_TP_301_ad1ab4ac3e.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Polyethylene glycol 3350 (PEG 3350) is used to treat occasional constipation and it is in a class of medications called osmotic laxatives. PEG 3350 is an addition polymer of ethylene oxide and water with formula H(OCH2CH2)n OH, in which n represents the average number of oxyethylene groups. The average molecular weight of PEG 3350 is 3015–3685 g/mol (Da). Acetaldehyde, Ethylene Oxide (EtO), 2-Chloroethanol (2-CE), Ethylene Glycol (EG), 1,4- Dioxane and Diethylene Glycol (DEG) are the probable impurities of PEG 3350. All these above impurities are highly toxic &amp; hazardous substances.&nbsp;</p><p>As per the USP monograph, different chromatography techniques and sample preparation methods are used to quantify above mentioned impurities. This study reports a single sensitive and reliable analytical method for quantitation of all above impurities by using dynamic headspace (Trap) coupled with GC-MS/MS system. Limit of impurities and detail method of analysis are shown in table 1.</p><p>This study reports highly sensitive single method for the simultaneous quantification of multiple probable impurities of PEG 3350 by using dynamic headspace (Trap) coupled with triple quadrupole gas chromatography (GC-MS/MS) system.&nbsp;</p><h4><strong>Materials and methods&nbsp;</strong></h4><p>For this study, individual impurity reference standards were procured from Sigma Aldrich, whereas PEG 3350 powder sample was procured from local medical store. 10% of PEG 3350 powder sample solution (as such sample solution) and respective levels of matrixmatched calibration standard solutions were prepared in acetonitrile. Standard addition method was used to quantify impurities in the PEG 3350 sample. This method was part validated with respect to (w.r.t) precision, linearity/accuracy and sample analysis. <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=GCMS-TQ8050+NX"><strong>GCMS-TQ8050 NX</strong></a> equipped with headspace sampler <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=HS-20+NX"><strong>HS-20 NX </strong></a>(Trap) (Figure 1), manufactured by Shimadzu Corporation Japan, was used to quantify impurities in the PEG 3350 sample</p><h4><strong>Conclusion</strong></h4><ul><li>Trace level quantification of Acetaldehyde, EtO, 2-CE, 1,4-Dioxane, EG and DEG in PEG 3350 sample was successfully performed by using Shimadzu GCMS-TQ8050 NX with HS-20 NX (Trap) dynamic headspace sampler.</li><li>Dynamic headspace mode outperforms the current regulatory limits, delivering multifold times more sensitivity compared to other injection techniques.</li><li>Shimadzu GCMS-TQ8050 NX features a new highly efficient detector and superior noise reduction technology that enhance sensitivity and enables quantitation of impurities even at trace levels.</li></ul>

News from LabRulezGCMS Library - Week 38, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 22nd September 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you application notes by <strong>Agilent Technologies, EST Analytical, Shimadzu </strong>and <strong>Thermo Fisher Scientific!</strong></p><h3><strong>1. Agilent Technologies: A Chemometric Approach for Ambient Air Monitoring Using Thermal Desorption GC/MS</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_voc_8890_chemometric_ambient_air_monitoring_5994_8451en_agilent_fef7d171bb.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Monitoring VOCs is crucial for assessing air quality in industrial and urban settings. These compounds, which include propene, hexachlorobutadiene, and naphthalene, vary in volatility and encompass both polar and nonpolar chemicals. Recognizing the importance of standardized monitoring, the Bureau of Indian Standards (BIS) has developed specific methodologies for these compounds under the IS 5182 series.&nbsp;</p><p>IS 5182-27 focuses on the measurement of vapor-phase organic chemicals such as vinyl chloride and nC22 hydrocarbons in air and gaseous emissions. This method employs diffusive (passive) sampling onto sorbent tubes or cartridges, followed by TD (see Figure 1) and capillary GC analysis. The passive sampling approach offers advantages in terms of ease of deployment and cost-effectiveness, making it suitable for widespread monitoring applications.</p><p>To reveal relevant patterns and sources of variation in these large environmental datasets according to the IS-5182 guidance, this application note proposes chemometric analysis using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=6&amp;search=TD100-xr"><strong>Markes TD100-xr automated thermal desorber</strong></a> (Figure 2) and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+gc"><strong>Agilent 8890 GC system</strong></a> with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977c"><strong>5977C GC/MSD</strong></a> (Figure 3). Chemometrics is a discipline that uses mathematics, statistics, and formal logic to design or select optimal experimental procedures. Chemometric techniques commonly used for clustering are the hierarchical agglomerative cluster analysis and PCA with factor analysis.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>This application note highlights the comparison of different air sampling strategies and shows their effect on qualitative and quantitative analysis of VOCs. Active (pumped) sampling helped with faster analysis, which is required for controlled and sensitive real-time monitoring of ambient air. Chromatograms of air sampled at various locations showed the presence of VOCs such as benzene, toluene, ethyl benzene, and xylenes. Many common and unique compounds were found at each location. The intensity of these compounds showed variations at different locations. Fewer compounds with lower intensities were observed in air samples from a residential area, whereas more compounds with higher intensities were observed in air samples from a traffic area.&nbsp;</p><p>Passive sampling was a comparatively cost‑effective and long-term approach and provided consistent replicate results. The chromatographic overlays of different sampling times indicated an increasing trend in peak intensities with respect to time. There was a considerable rise in peak intensities for the 1-week sampling period, as compared to 24-hour sampling. There was a slight rise in peak intensities for the 2-week sampling period, as compared to 1-week sampling. The PCA plot suggested the peak distribution obtained in each dataset. One-week sampling results showed consistent replicate results. Use of the chemometrics software Agilent Mass Profiler Professional added value by providing data visualization for interpretation.</p><h3><strong>2. EST Analytical: USEPA 524.2 Method Validation Using the Evolution Purge and Trap Concentrator and the Centurion WS Autosampler</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_524_2_Application_Note_2d327854f2.pdf"><strong>Full PDF for download</strong></a></li></ul><p>USEPA Method 524.2 calls for purge and trap sampling coupled with a Gas Chromatograph (GC) and Mass Spectrometer (MS) for separation and analysis. It has an extensive list of compounds and requires lower detection limits due to its use in drinking water testing. A 20% relative standard deviation for compound response factors is required across the calibration curve while the calibration check standard analytes have to be within 30% of the expected concentration.&nbsp;</p><p>Currently, this method calls for a 5mL or 25mL purge volume and a four minute desorb time. These method requirements can pose a challenge for the analyst due to the amount of moisture that is created. The negative effects of the increased water vapor include instability of the chromatography, band eluting and poor peak shape to name a few. A side effect of this instability is sample re-runs and lost laboratory productivity. In addition, a common practice for mitigating moisture is increasing the GC inlet split rate. This poses yet another difficulty as the increased split rate can result in reduced sensitivity. EST Analytical’s eight port valve in the Evolution purge and trap concentrator aids in limiting the water exposure because the water management of the system is not part of the desorb pathway. This feature also enables laboratories to use a smaller split ratio at the GC inlet thus increasing sensitivity.</p><h4><strong>Experimental</strong></h4><p>The sampling system used for this study was the<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong> EST Analytical Evolution purge and trap concentrator </strong></a>and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS autosampler</strong></a>. The concentrator was affixed with a Vocarb 3000 trap and connected to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890A"><strong>Agilent 7890A GC</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C"><strong>5975C inert XL MS</strong></a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=9&amp;search=Rxi-624+Sil+MS"><strong>Restek Rxi-624 Sil</strong></a> MS 30m x 0.25mm x 1.4µm column. Sampling parameters are listed in Table 1 while Table 2 enumerates the GC/MS parameters.</p><h4><strong>Conclusions</strong></h4><p>This study demonstrated the effectiveness of the Evolution/Centurion purge and trap sampling system. The results passed all of the USEPA Method 524.2 criteria for both linearity and detection limits. Since the Evolution bypasses the water management trap during the four minute desorb process, the amount of water effecting the experiments was limited. Furthermore, the forty to one split ratio at the GC inlet provided excellent detection limits as the system was more sensitive to the low level standard requirements of the method. The lower split rate has an added benefit of reducing laboratory helium consumption when setting it against other system’s higher split ratios. Finally, the precision and percent recovery results showed the reliability of the system in producing accurate experimental findings.</p><h3><strong>3. Shimadzu: Dual-Column Analysis of Blood AlcoholContent (BAC) Using Nitrogen Carrier Gas with </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050"><strong>Brevis GC-2050</strong></a></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00899_en_af0d9bafe7.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Analysis of blood alcohol content (BAC) and other volatile organic compounds (VOCs) is essential for law enforcement agencies to determine alcohol intoxication and its role in traffic accidents, assaults, and injuries, as well as to identify the causes of certain criminal behaviors, poisonings, and so on.&nbsp;</p><p>Typically, this analysis is performed by a gas chromatograph (GC) that is combined with a headspace sampler (HS) and a flame ionization detector (FID). Since accurate results are essential with BAC analysis, 2 columns can be used with different separation characteristics so that cross-checking can be performed. By using an integrated HS-GC system equipped with 2 FIDs connecting to a dual-column configuration, crosschecking can be performed in a single analysis. In this system, the columns are directly connected to the transfer line using a 2-hole ferrule, which minimizes sample losses due to adsorption.&nbsp;</p><p>In addition to the high-end <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis+GC-2030"><strong>Nexis GC-2030</strong></a>, Shimadzu also offers the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050"><strong>Brevis GC-2050</strong></a> as a compact gas chromatography solution, and in this Application News, it is used with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20+NX+headspace+sampler"><strong>HS-20 NX headspace sampler </strong></a>(Fig. 1) to perform BAC analysis. Hydrogen was used as the carrier gas in a similar experiment in Application News 01-00570, but in this experiment, nitrogen was used because it is a cheaper alternative carrier gas. Nitrogen generally has an adverse effect on separation, so this experiment also investigated the conditions for separation for 10 types of blood VOCs.</p><h4><strong>Separation of 10 Blood VOCs&nbsp;</strong></h4><p>A solution of 10 VOCs spiked with blood (0.1 mg/mL) was analyzed to determine the separation of methanol, acetaldehyde, ethanol, isopropyl alcohol, acetonitrile, acetone, tert-butanol, 1-propanol, methyl ethyl ketone, and ethyl acetate. The resulting chromatogram is shown in Fig. 6. All peaks were detected within 6.0 minutes in the BAC PLUS1 column and within 3.5 minutes in the BAC PLUS2 column, indicating good separation. The elution sequence of the 10 blood VOCs differed significantly between the columns, which enhanced the system’s qualitative capability. Table 4 shows the retention time of each compound and the repeatability (n=5) of the peak area ratio for the tert-butanol internal standard.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>This experiment involved dual-column analysis of blood alcohol content (BAC) by the compact Brevis GC-2050 and the HS-20 NX. Dual-column configuration enables cross-checking in a single analysis. In addition, nitrogen was used as the carrier gas instead of helium. While hydrogen enables high-speed analysis, it also requires careful handling, so from the perspective of safety, installation of various optional tools such as hydrogen sensor and stop valve have been recommended. Nitrogen gas is relatively inexpensive and easy to handle, and this experiment demonstrated that it also provides reliable results while maintaining good separation.</p><h3><strong>4. Thermo Fisher Scientific: Routine analysis of 7N high purity gallium phosphide by Glow Discharge Mass Spectrometry</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_003578_ioms_gd_ms_element_gd_plus_gallium_an003578_em_en_1666255eb4.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Gallium phosphide (GaP) is a semiconductor material used in electronic and optoelectronic devices, including light-emitting Diodes (LEDs), solar cells as well as high-frequency and high-power electronics<sup>1-5</sup>. GaP wafers offer several advances over traditional silicon wafers, including high efficiency, high-speed operation, and highpower handling capabilities<sup>4-5</sup>.&nbsp;</p><p>This application note describes the direct analysis of impurities in high purity gallium phosphide with sub-ppb detection limits using the Thermo Scientific <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/1690"><strong>Element GD PLUS GD Mass Spectrometer</strong></a>.&nbsp;</p><h4><strong>Experiment&nbsp;</strong></h4><p>The flat samples are analyzed directly, with no digestion required. Instrumental conditions for the analysis with the Element GD PLUS GD-MS are shown in Table 1. Potential sample surface contaminations were removed by short presputtering within the instrument.&nbsp;</p><h4><strong>Method development&nbsp;</strong></h4><p>The developed method ensures a reliable separation of interferences from the analyte ions. The interferences PO, POH and GaGa could potentially lead to falsely high Ti, Ba and Ce results. The formation of these interferences is low in the fast-flow source of the Element GD PLUS GD-MS: 69Ga69Ga/69Ga ≈ 1 ppm and ( 31P16O1 H + 31P17O)/31P ≈ 10 ppm. They can easily be resolved at Medium Mass Resolution (R = M / Δm = 4000). This is visualized in the mass scans shown in Figures 1 and 2 with much wider mass windows than later being used for quantification. Therefore, the Medium Mass Resolution of the Element GD PLUS GD-MS enables interference free measurements of Ti, Ba and Ce in GaP matrix.</p><h4><strong>Conclusions&nbsp;</strong></h4><p>Trace contaminations in 7N high purity gallium phosphide can be determined reliably and routinely with the Element GD PLUS GD-MS without prior digestion.&nbsp;</p><p>While most analytes like Ti, Ba and La are resolved from interferences in medium mass resolution (R = 4000), high mass resolution (R = 10000) is required for Ag because of the GaAr interference. Sub-ppb detection limits, even for elements like Sb and Ge, are achieved by neglectable formation of triatomic interferences and reduced abundance sensitivity. That is enabled by the fast-flow source design and the reverse Nier-Johnson geometry.</p><p>Semiquantitative quantification of element concentrations can be performed without standard reference materials using the standard RSF factor approach. The high sensitivity of the instrument, the reliable separation of interferences in medium and high mass resolution, the outstanding peak stability, the low formation of interferences and the low abundance sensitivity enable limits of detection of 0.05 to 1 ppb for most elements.&nbsp;</p><p>The sum of all impurities in the GaP sample was below 50 ppb, implying that a purity of 7N GaP can be assessed with the instrument.</p>

News from LabRulezGCMS Library - Week 39, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 29th September 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you application notes by <strong>Agilent Technologies </strong>and<strong> EST Analytical, </strong>poster by<strong> Shimadzu </strong>and smart note by <strong>Thermo Fisher Scientific!</strong></p><h3><strong>1. Agilent Technologies: Equimolar Response to ASTM D5623 Relevant Sulfur Compounds</strong></h3><p><strong>Using an </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC"><strong>Agilent 8890 gas chromatograph</strong></a><strong> and </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8355%C2%A0SCD"><strong>8355 sulfur chemiluminescence detector (GC/SCD)</strong></a></p><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_equimolar_response_astm_d5623_sulfur_compounds_5994_8562en_agilent_62a37181e4.pdf"><strong>Full PDF for download</strong></a></li></ul><p>For many years, the use of a sulfur-specific detector in the petroleum industry has been invaluable for accurately identifying low levels of sulfur-containing compounds in petroleum at various stages of production.<sup>1</sup> Many environmental and health requirements limit the amount of sulfur allowed in the final petroleum product. The presence of sulfur also has the potential to poison the catalytic processes that take place during petroleum refining.&nbsp;</p><p>Along with the determination of low sulfur levels in a petroleum sample, a detector may also need to measure high sulfur levels and total sulfur content. A detector with a high linear range is essential in making both low-level and high‑level determinations of sulfur in a petroleum sample.&nbsp;</p><p>In this application note, an Agilent 8355 SCD was used to measure 19 sulfur-containing compounds within a standard sample. The 8355 SCD is ideal for the widely used ASTM&nbsp;D5623 method<sup>2</sup> because of its ability to obtain linear and equimolar responses to sulfur compounds with minimal hydrocarbon interference. When comparing the equimolar response of analytes containing different numbers of sulfur atoms, the response should be double for the analytes containing two sulfur atoms compared to those with one&nbsp;sulfur atom.&nbsp;</p><p>Another advantage of the 8355 SCD is the ability to use it in tandem with an FID. This combination allows monitoring solvent elution through the GC system, assisting in the detection of the coelution of solvents with analyte peaks. These coelutions can cause peak distortion, which might be mistaken for activity issues within the GC system.</p><h4><strong>Methods&nbsp;</strong></h4><h5><strong>Instrumentation&nbsp;</strong></h5><p>Two <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC"><strong>Agilent 8890 GC systems</strong></a> were equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8355%C2%A0SCD"><strong>8355&nbsp;SCD</strong></a>. Both GC/SCD systems were run in the same manner to confirm equimolar results. A third GC system was also configured with a tandem flame ionization detector sulfur chemiluminescence detector (FID/SCD) to allow the determination of the solvent peak elution from the system. This third system also served as another confirmation of the equimolar results that were obtained from the other two GC/SCD systems. Sample introduction for all systems was completed with an Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7693A+automatic+liquid+sampler"><strong>7693A automatic liquid sampler</strong></a> with a 5 µL syringe. The sample volume for each injection was 1.0 µL. All analyses were performed with a split/splitless inlet in split mode.&nbsp;</p><p>The GC/SCD parameters are provided in Table 1. Note that an Agilent DB-Sulfur SCD GC column (part number G3903-63002) was used in this study because of the low column bleed and excellent inertness and performance for sulfur compound analysis. When using the SCD, be aware that stationary phase bleed from the GC column can lead to fouling of the ceramic tubes within the detector. This phenomenon can cause poor SCD performance, such as decreased sensitivity, and may require more frequent maintenance. Proper GC column selection (such as the DB-Sulfur column) is important to ensure lower column bleed into the detector and will reduce fouling of ceramic tubes, reducing instrument downtime.</p><h4><strong>Results and discussion</strong></h4><h5><strong>Use of GC/FID for solvent elution determination&nbsp;</strong></h5><p>Determination of the solvent peak elution can be a challenge when using a sulfur-selective detector such as the SCD. Many times, the large, fronting solvent peak may coelute with analytes of interest, causing distortion of the analyte peak shape (peak tailing, fronting, or broadening) and poor chromatographic separation. This poor peak shape, caused by column overloading, can be mistaken for activity issues in the system or hydrocarbon interferences, leading to unnecessary troubleshooting or inlet/column maintenance. Determination of the solvent peak elution time is recommended to ensure that coelution does not occur with any of the analytes of interest. To confirm the solvent elution time, a tandem GC/FID/SCD system was used. The GC/FID/SCD system puts the FID in-line before the SCD analysis, allowing the user to obtain both FID and SCD signals from a single injection, thus confirming the solvent retention time and determining any solvent/analyte coelutions.&nbsp;</p><h4><strong>Conclusion&nbsp;</strong></h4><p>The Agilent 8355 sulfur chemiluminescence detector, paired with an Agilent 8890 GC, was evaluated by analyzing 19&nbsp;sulfur‑containing compounds relevant to ASTM D5623. The SCD met the specifications of the test method, including an equimolar response to the analyzed sulfur compounds and a wide range of linearity to a sulfur-containing standard. The 8355 SCD shows excellent area reproducibility, and when used in tandem with a flame ionization detector, the system can aid in the determination of solvent peak elution through the GC system.</p><h3><strong>2. EST Analytical: Reducing Carryover in Environmental Water Samples</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_Reducing_Carryover_in_Environmental_Water_Samples_6e5ba0a008.pdf"><strong>Full PDF for download</strong></a></li></ul><p>In order to mitigate carryover, many environmental labs resort to running sample dilutions or adding blank samples after a highly contaminated sample. Both of these solutions are not ideal and can lead to a loss of analyte detection when diluting or a loss of profits when blank samples need to be run.</p><p>Since, the primary source of carryover for water samples is the sparge vessel, purge and trap manufactures have incorporated a rinsing step in which the sparge vessel is “washed” with hot water in order to clean up the volatile compounds that may still reside in the sparge vessel. Expanding on the idea of limiting volatile compounds in the sparge vessel, EST Analytical developed a patented process of heating the sparge vessel during the bake step of the purge and trap process (Patent Number: US 8,075,842 B1) . This engineering innovation essentially performs two bakes; as a result both the trap and the sparge vessel are “cleaned” at the same time. No other concentrator is or can be engineered to do this.</p><h4><strong>Experimental</strong></h4><p>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>EST Analytical Evolution concentrator</strong></a> and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS autosampler</strong></a>. The concentrator was affixed with a Vocarb 3000 trap and connected to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890A"><strong>Agilent 7890A GC </strong></a>and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C"><strong>5975C inert XL MS</strong></a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=9&amp;search=Rxi-624+Sil+MS"><strong>Restek Rxi-624 Sil</strong></a> MS 30m x 0.25mm x 1.4µm column. Refer to Table 1 for the sampling method parameters and Table 2 for GC/MS parameters.</p><h4><strong>Conclusions</strong></h4><p>The Evolution purge and trap concentrator with its patented technique of heating the sparge vessel during the bake process proved to reduce carryover by almost half when comparing with hot water rinses alone. The advantages of reduced carryover are many. Primary among them is the ability to run more samples during the twelve hour tune window. This increase in productivity translates to more laboratory profits and better use of instrument time.</p><h3><strong>3. Shimadzu / AOAC: Analysis of PFAS in juice using Head-Space Solid Phase Microextraction-Gas Chromatography/Mass Spectrometry (HS-SPME GCMS)</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/aoac_2025_t010_9967ebebff.pdf"><strong>Full PDF for download</strong></a></li></ul><p>PFAS contaminate water and food through packaging that can leach volatile PFAS from plastics and inks or coatings. This work developed a headspace SPME GCMS method to analyze six volatile PFAS classes in juices. The United States Food and Drug Administration has tested for PFAS in a broad range of foods and beverages as part of its Total Diet Study. Juice matrices differ in flavor, sugar, as well as manufacturing practices, and packaging, with the latter two potentially introducing PFAS contamination. The former differences between products can impact PFAS detection.</p><h4><strong>Materials and Methods</strong></h4><p>The SPME method used in this study is based on a method published by Bach et.al. (2016). An HS-SPME method is used to improve method performance when analyzing complex aqueous samples over direct immersion. The optimized parameters of the instrument method for the targeted PFAS are listed in table 1.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=GCMS-TQ8040+NX"><strong>Shimadzu GCMS-TQ8040 NX triple quadrupole instrument</strong></a>, configured with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=AOC-6000+Plus+SPME"><strong>AOC-6000 Plus SPME</strong></a> unit, was used to measure PFAS in different juice samples. Without isotope dilution, matrix effects caused recoveries to fall outside of acceptable criteria. Method blanks showed no detectable PFAS, and calibration demonstrated excellent linearity (R² ≥ 0.993). This HS-SPME GCMS-TQ8040 NX method demonstrated quantitative capability for analyzing nanogram-per-liter PFAS compounds in complex juice matrices. This application highlights a simple, fast, robust, precise, and accurate workflow for measuring volatile PFAS in challenging matrices.</p><h3><strong>4. Thermo Fisher Scientific: Safe use of carrier hydrogen for air monitoring with Multi-Gas TD-GC-MS</strong></h3><ul><li>Other document (smart note)</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/sn_003958_gc_single_quad_gc_ms_isq_7610_environmental_sn003958_na_en_8216fc7021.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Monitoring volatile organic air compounds, also known as hazardous air pollutants (HAPs), is crucial for maintaining air quality in urban and industrial environments due to their significant health risks. The growing concerns about these potentially dangerous volatile organic compounds in ambient air, particularly in urban areas and from industrial emissions, have led to the development of numerous national and international regulations. The use of Thermal Desorption (TD) coupled with GC-MS is the analytical technique of choice to enrich volatile organic compounds from air and quantify them at trace levels.1 In gas chromatography, the choice of carrier gas is pivotal for the separation and detection of VOCs. Helium has traditionally been the preferred carrier gas for analyzing volatile organic air toxics due to its inertness and performance benefits. However, hydrogen is becoming increasingly popular due to economic and supply considerations. Each carrier gas has unique advantages and challenges, and the choice should be guided by specific analytical requirements, cost constraints, and safety protocols. As the demand for sustainable and cost-effective solutions grows, hydrogen is expected to play a more significant role in monitoring hazardous air pollutants in urban and industrial settings.</p><p>Thermal Desorption is an established way to analyze VOCs in a wide variety of sample types. This smart note highlights the use of the new Multi-Gas TD system (Markes International) that allows a safe use of carrier hydrogen for the analysis of VOCs in air, enhancing operational flexibility and supporting more sustainable laboratory practices.&nbsp;</p><h4><strong>Experimental&nbsp;</strong></h4><p>In this study, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=7&amp;search=TD100-xr"><strong>Markes TD100-xr™ Multi-Gas system</strong></a>, coupled with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/486"><strong>Thermo Scientific™ TRACE™ 1610 gas chromatograph</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/484"><strong>Thermo Scientific™ ISQ™ 7610 single quadrupole mass spectrometer,</strong></a> was employed to accurately detect and quantify compounds for effective air monitoring. This combination leverages several technological advancements to optimize analytical performance and operational efficiency.</p><p>The comparison between helium and hydrogen carrier gas was carried out using the same analytical column. The method conditions for all analytes could be easily transferred. Flow rates were adjusted using the split ratio calculator available in the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/76"><strong>Thermo Scientific™ Chromeleon™ Chromatography Data System (CDS)</strong></a> Instrument Method Wizard (Figure 1) to maintain the same split level and therefore the same amount of transferred sample. A further factor facilitating rapid adoption of hydrogen carrier gas in laboratories is that existing columns and consumables can be used without restrictions.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>The use of the Markes TD100-xr Multi-Gas system combined with the ISQ 7610 GC-MS for the analysis of VOC in air allows for a safe use of carrier hydrogen, making it a viable alternative to helium and offering an effective solution for laboratories facing the challenges of helium scarcity and rising costs, while maintaining the accuracy and reliability of VOC detection and quantification.&nbsp;</p><ul><li>The comparative analysis clearly confirmed that using hydrogen carrier gas in gas chromatography offers substantial benefits over helium. The significant reduction in retention time, as shown by the 60% decrease for 1,2,3-trichlorobenzene, leads to faster analysis without compromising the separation efficiency.&nbsp;</li><li>Enabling shorter analysis time, hydrogen enhances laboratory productivity, reduces costs, and contributes to more sustainable practices.&nbsp;</li><li>The results also indicate that both helium and hydrogen can be used effectively as carrier gases without impacting the response linearity for the VOC compounds under evaluation. Laboratories can confidently use hydrogen as an alternative to helium for quantitative analysis, ensuring accurate and reliable analytical results.</li><li>When using multiple carrier gases, the ISQ 7610 NeverVent technology is key to easily switching from helium to hydrogen and back to helium with no venting required, making this operation very quick and safe.&nbsp;</li></ul><p>In conclusion, coupling the Markes TD100-xr Multi-Gas system with the ISQ 7610 single quadrupole GC-MS offers a robust and flexible solution for air monitoring. This integration enhances operational efficiency, reduces costs, and maintains high data integrity, making it an invaluable tool for modern analytical laboratories.</p>

News from LabRulezGCMS Library - Week 40, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 13th October 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you poster by <strong>Agilent Technologies / AOAC </strong>and<strong> </strong>application notes by<strong> EST Analytical, Shimadzu </strong>and <strong>Thermo Fisher Scientific!</strong></p><h3><strong>1. Agilent Technologies / AOAC: Analysis of Pesticides in Spices with Hydrogen Carrier Gas</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_pesticides_hydrogen_carrier_gas_aoac_2025_w007_en_agilent_280dd876d5.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Spices are considered as one of the most challenging matrices for analysis of pesticides. Usually, the sample analysis involves 5-10 fold dilution to reduce the matrix load. Thus, lower instrument detection limits need to be achieved. Use of hydrogen as carrier gas can further pose changes in terms of sensitivity. This work describes the suitability of the hydroinert and HES ion source to achieve the required sensitivity. Samples were extracted using QuEChERS based approach followed by dispersive cleanup. Linearity was evaluated against matrix matched standards within the range of 0.5-50 ng/mL. Correlation coefficient (r2) for calibration ranging between 0.5 -50 ng/mL was found above 0.95. Precision study was carried out by injecting 6 replicates of pre-spiked samples at 10 ng/g. The average relative standard deviation (%RSD) was &lt;20% with recoveries ranging from 72-125%. The advantages of the method include utilization of same retention time MRMs and collision energies. This allowed for easy transition from helium to hydrogen carrier gas.</p><h4><strong>Experimental</strong></h4><p>An Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC"><strong>8890 GC</strong></a> coupled to a 7000 (with HydroInert source) / <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7010+Triple+Quadrupole+GC%2FMS"><strong>7010 Triple Quadrupole GC/MS</strong></a> system equipped with High Efficiency Source (HES) was used. The GC system was equipped with a MultiMode Inlet (MMI) with air cooling and a back flushing system based on a Purged Ultimate Union controlled by a PSD module.</p><h4><strong>Results and Discussion&nbsp;</strong></h4><p>The oven temperature program used with H2 as the carrier gas was maintained identical to that used with He. The analytical method originally optimized for a 20- minute runtime using He was successfully adapted for H2. This ensured preservation of chromatographic resolution and retention time fidelity across carrier gas substitution, as evident from the elution order shown in Figure 3. The chromatograms indicate presence of high matrix load at initial 7 mins for all the spices. At RT 10-13 min, matrix load of and chilli was high. The matrix load from black pepper was very high throughout the runtime. Backflush of 7 min was used to remove the matrix.&nbsp;</p><p>Transitioning from He to H2 can often lead to reactions at the ion source resulting in spectral changes when compared with He. Therefore, EI sources with reduced or eliminated source reactivity such as HydroInert and HES is essential to minimize or prevent the undesirable insource reactions when using hydrogen. The tested mixture of pesticides were compared against the NIST library to ensure spectral fidelity. As evident form Figure 5, the library match percentages were acceptable and this the existing MRM database could be used for acquisition in MRM mode, without the requirement of any additional MRM development.</p><h4><strong>Conclusions</strong></h4><p>Agilent GC/TQ systems with HydroInert and HES sources delivered consistent sensitivity and spectral fidelity using hydrogen carrier gas, without re-optimizing MRM transitions or collision energies. Retention times and elution order were preserved across complex spice matrices. The systems achieved LOQs of 2.5 to 5 ppb after five-fold dilution, even in heavily loaded matrices like black pepper, confirming reliable quantitation in high-background spice samples.</p><h3><strong>2. EST Analytical: A Single Calibration Method for Water AND Soil Samples Performing EPA Method 8260</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_A_Single_Calibration_Method_for_Water_AND_Soil_Samples_Performing_EPA_Method_8260_27f8b93aad.pdf"><strong>Full PDF for download</strong></a></li></ul><p>In order to run Method 8260 samples, a bromofluorobenzene (BFB) tune standard, matrix blank, calibration standard, and laboratory control standard all have to be run and pass method requirements every twelve hours. With the exception of the BFB standard, the other standards and blank matrices have to correspond to the samples to be analyzed. Due to this constraint, the analyst is required to run another three samples if the matrix is changed within the twelve hour time window. Moreover, the calibration must also match the sample matrix. These requirements are very time consuming and can limit laboratory profits. This application note will demonstrate a patented automated water sampling mode using the soil sampling station of the autosampler thus eliminating the need to have separate calibrations and standards for waters and soils.</p><h4><strong>Experimental</strong></h4><p>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>EST Analytical Centurion WS autosampler</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>Evolution concentrator</strong></a>. The concentrator was affixed with a Vocarb 3000 trap and connected to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890A"><strong>Agilent 7890A GC</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?search=5975"><strong>5975 inert XL MS</strong></a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=9&amp;search=Rxi-624+Sil+MS"><strong>Restek Rxi-624 Sil MS </strong></a>30m x 0.25mm x 1.4µm column. The experiments were run using the extraction mode of the Centurion WS. Refer to Table 1 for the sampling method parameters and Table 2 for GC/MS parameters.</p><h4><strong>Conclusion</strong></h4><p>The patented sampling process of the Centurion WS proved to be a reliable and accurate sampling method for running water samples in the soil mode. The curve linearity and method detection limits both met USEPA Method 8260 requirements, and the precision and accuracy results were excellent. The water extraction option offered with the Centurion WS will save laboratories time and money because only one set of standards, curves, etc. is required for both water and soil samples.</p><h3><strong>3. Shimadzu: Measurement of Volatile Organic Compounds in Water by Headspace GC-MS with Nitrogen Carrier Gas</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00907_en_077ab0a675.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Due to the health issues associated with volatile organic compounds (VOCs), standards and regulations are established for VOC levels in water. VOCs are preferably measured by methods that involve simple sample pretreatment, and headspace GC-MS is one of these methods commonly used to measure VOC levels. GC-MS is normally performed with helium carrier gas, but helium gas could require more cost and lead time to obtain for analytical use every year. There is a need for a GC-MS analysis method that can be performed using relatively inexpensive and readily available nitrogen carrier gas. While nitrogen carrier gas results in inferior analytical sensitivity compared with helium carrier gas, trap mode sampling can salvage the reduction of the sensitivity. This Application News presents an example measurement of VOCs in water using nitrogen carrier gas performed on the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a> gas chromatograph mass spectrometer and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20+NX"><strong>HS-20 NX headspace sampler</strong></a> in trap mode.</p><h4><strong>Samples and Analysis Conditions&nbsp;</strong></h4><p>Standard solutions were prepared by diluting 25 standard VOC mixture in methanol to 1, 2.5, 5, 10, 25, 50, 100, and 250 mg/L. The standard solutions were combined with internal standards 1,4-dioxane-d8 at 100 mg/L, fluorobenzene at 12.5 mg/L, and pbromofluorobenzene at 12.5 mg/L.</p><ul><li><strong>GC-MS: </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050"><strong>GCMS-QP2050</strong></a></li><li><strong>Head Space Sampler: </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20+NX"><strong>HS-20 NX</strong></a></li></ul><h4><strong>Conclusion&nbsp;</strong></h4><p>VOC levels in water were measured using an HS-20 NX in trap mode and a GCMS-QP2050 with nitrogen carrier gas. Trap mode allowed VOCs to be measured in water with a high degree of sensitivity, even with nitrogen carrier gas.</p><h3><strong>4. Thermo Fisher Scientific: Enhanced trace moisture analysis in organic solvents using GC with multi-channel VUV detection</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_003954_gc_luma_detector_trace_1610_industrial_pharma_an003954_na_en_c29f4875a6.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Monitoring water content in organic solvents is essential across various industries, notably in pharmaceutical manufacturing, where excess moisture can compromise active ingredient stability. Traditionally, Karl Fischer titration has been the benchmark technique, offering broad quantification capability. However, KF is limited by side reactions, reagent sensitivity, and incompatibility with high-throughput workflows. It also relies on hazardous solvents and extensive manual steps.&nbsp;</p><p>Gas chromatography provides an alternative means of quantifying water when paired with an appropriate detector. While FID and TCD have been used, they lack the selectivity and sensitivity required for trace moisture detection. Ionization-based detectors like PDD improve detection but suffer from dynamic range limitations.</p><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=3&amp;search=LUMA%E2%84%A2+VUV+detector"><strong>LUMA™ VUV detector </strong></a>(VUV Analytics, Inc.) overcomes these drawbacks by employing vacuum ultraviolet absorbance in the 118–240 nm range, where water exhibits strong and selective absorption. Unlike other GC detectors, LUMA combines universality, spectral selectivity, and ease of use in a single platform.&nbsp;</p><p>This work illustrates a GC method using a LUMA Multi-Channel VUV Absorbance detector to analyze moisture in acetonitrile from 250 ppb up to percent levels. This approach has several advantages over traditional techniques like Karl Fischer titration, including superior sensitivity for the analysis of trace levels of water in acetonitrile as well as percent levels. The achievable limit of detection for water in acetonitrile is 250 ppb, with method linearity over 0.25–100 ppm producing R² ≥ 0.999.&nbsp;</p><h4><strong>LUMA detector highlights&nbsp;</strong></h4><ul><li><strong>Detection range: </strong>125–1,050 nm VUV-UV-VIS&nbsp;</li><li><strong>Channel configuration:</strong> Up to 12 discrete absorbance bands simultaneously acquired&nbsp;</li><li><strong>Sensitivity: </strong>Low-ppb to percent level in a single method&nbsp;</li><li><strong>Installation: </strong>Compact, uses any carrier gas and no vacuum pumps&nbsp;</li><li><strong>Software integration: </strong>Fully controlled via Thermo Scientific™ Chromeleon™ Chromatography Data System (CDS)&nbsp;</li></ul><p>These capabilities enable detection of water and organic solvents in a single injection—dramatically simplifying workflows in quality control laboratories.</p><h4><strong>Experimental&nbsp;</strong></h4><p>The LUMA detector can be easily installed on a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/483"><strong>Thermo Scientific™ TRACE™ 1600 Series GC</strong></a> and controlled in <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/76"><strong>Chromeleon CDS</strong></a>, providing method settings, data acquisition, and reporting in a single software platform.</p><p>GC-VUV separation using the LUMA Multi-Channel Vacuum Ultraviolet Absorbance detector was based on a previously described method by VUV Analytics.¹ Method conditions for this experiment are described in Table 1.</p><p>A commercially available 100 ppm KF standard (water in xylene) was used to determine sensitivity, linearity, and repeatability. To minimize the impact of environmental moisture in this experiment, the same solution has been used to simulate different water levels through varying split ratios and injection volumes.&nbsp;</p><p>Seven concentration levels (0.25–100 ppm) were created using adjusted split ratios as summarized in Table 2. Five replicate injections were made at each level.</p><h4><strong>Key application benefits&nbsp;</strong></h4><ul><li>Replaces Karl Fischer titration for routine moisture analysis&nbsp;</li><li>Simultaneous quantification of water and organic solvents&nbsp;</li><li>Ideal for pharmaceutical QA/QC and regulatory environments&nbsp;</li><li>Fast, automated workflows with no vacuum or specialty gases&nbsp;</li></ul><p>This workflow is aligned with recent trends toward hybrid analytical techniques that reduce resource consumption and speed up decision-making in GMP labs.&nbsp;</p><h4><strong>Conclusion</strong></h4><p>The LUMA multi-channel VUV detector offers a transformative approach to moisture analysis in volatile organic solvents. It provides both trace-level sensitivity and wide dynamic range— enabling labs to consolidate workflows, eliminate time-consuming titrations, and enhance data reliability.&nbsp;</p><p>By expanding GC capability to encompass water detection, LUMA bridges a long-standing gap in chromatographic technology, delivering measurable gains in efficiency and analytical scope.&nbsp;</p><ul><li>The detector operates in the 125 nm to 1,050 nm region of the spectrum, where nearly all compounds absorb, making it a universal GC detector.&nbsp;</li><li>The detector associates high sensitivity to high selectivity thanks to the simultaneous acquisition of 12 channels with different spectral range in the VUV spectrum.&nbsp;</li><li>Working with up to 12 channels, the detector allows the determination of multiple analytes in a single injection. For example, water, solvents, and a range of impurities including potential genotoxic impurities (PGIs).&nbsp;</li><li>In addition to having high sensitivity and selectivity, the LUMA detector is easy to use; it is controlled by Chromeleon CDS, fitting well into existing laboratory workflows, and does not require a vacuum pump or separate special carrier gases.</li></ul>

News from LabRulezGCMS Library - Week 42, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 20th October 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you applicaton notes by <strong>Agilent Technologies, EST Analytical, Shimadzu </strong>and <strong>Thermo Fisher Scientific!</strong></p><h3><strong>1. Agilent Technologies: FAMEs Analysis of Oils by GC-FID Coupled with Fully Automated Sample Preparation using a PAL3 Series 2 RTC</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_fame_oil_gc_pal3_5994_8543en_agilent_418da94d17.pdf"><strong>Full PDF for download</strong></a></li></ul><p>The analysis of fatty acid methyl esters (FAMEs) is a widely used technique for characterizing lipid profiles in various food products, including oils, meats, and seeds. Fats are composed of a complex mixture of saturated, monounsaturated, and polyunsaturated fatty acids, each with varying carbon chain lengths.2 This type of analysis is routinely performed in governmental, quality control (QC), and contract research laboratories worldwide. The resulting data often informs product labeling. Among the analytical techniques available, gas chromatography (GC) with flame ionization detection (GC-FID) is one of the most common methods for determining fatty acid composition in&nbsp;foods.&nbsp;</p><p>This application note describes the use of automated sample preparation and analysis of FAMEs using the PAL3 Series&nbsp;2 RTC Autosampler system coupled with Agilent 8890 GC system equipped with an FID. The results shown here focus on two different methods of derivatization for FAMEs extraction: (1) base catalyzed reactions using potassium hydroxide (KOH) (part&nbsp;number M5795-14000) and (2) base plus acid catalyzed reactions using boron trifluoride (BF3 ) 1 (part number M5795-14001). For ease of use, both processes have been transcribed into dedicated sample preparation methods. These methods are part of the Agilent automated sample preparation workflow suite of solutions. These workflows improve process safety, optimizes throughput, and minimizes&nbsp;errors.</p><h4><strong>Experimental&nbsp;</strong></h4><p>The 37 component FAME mix standard was purchased from Sigma-Aldrich (part number CRM47885), and three consumer oil products were purchased from a local grocery store. The samples were prepared and injected into the GC using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=PAL3"><strong>PAL3 Series 2-RTC system</strong></a>. The analysis was performed using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC"><strong>8890 GC</strong></a> equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB%E2%80%91FastFAME"><strong>Agilent DB‑FastFAME GC column</strong></a>, 30&nbsp;m × 250 µm, 0.25&nbsp;µm, (part number G3903‑63011) and configured with an FID using Agilent&nbsp;<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=OpenLab+CDS+v2.7"><strong>OpenLab CDS v2.7+</strong></a>.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>In summary, the current study demonstrated excellent reproducibility and accuracy using automated sample preparation and analysis of FAMEs. Two different sample preparation methods were demonstrated, both delivering comparable and reliable results. The base-catalyzed method enables rapid analysis but is not suitable for samples containing free fatty acids. In contrast, the acid-catalyzed method, while more extensive, is compatible with a broader range of lipid classes, including free fatty acids, phosphoglycerides, and triglycerides. The Agilent automated sample preparation workflow suite of solutions deliver a comprehensive package by combining preconfigured hardware, optimized analytical methods, and the necessary consumables to ensure efficient and reliable results.</p><h3><strong>2. EST Analytical: Unregulated Contaminant Monitoring Rule 3 for USEPA Method 524.3 and 524.4</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_Unregulated_Contaminant_Monitoring_Rule_3_for_USEPA_Method_524_3_and_524_4_b774e6ab4c.pdf"><strong>Full PDF for download</strong></a></li></ul><p>The third Unregulated Contaminant Monitoring Rule (UCMR 3) was finalized in April of 2012. UCMR 3 requires public water systems to monitor for a specific list of 30 contaminants under three separate lists: list one, assessment monitoring, list two, screening survey, and list three, pre-screen testing. This application note will address the volatile organic compounds found in list one, assessment monitoring contaminants. USEPA Method 524.3 and 524.4 will be the methods evaluated for sampling and analysis.</p><h4><strong>Discussion&nbsp;</strong></h4><p>The amendments to the Safe Drinking Water Act (SDWA) require the EPA to list no more than 30 unregulated contaminants to be monitored by public water systems. Every five years, this list needs to be updated. List one contaminants include seven volatile organic compounds to be analyzed by USEPA Method 524.3. The detection limits for these compounds are much lower; therefore, Single Ion Monitoring (SIM) must be used for compound detection. USEPA Method 524.3 and 524.4 allow for modification of purge and trap parameters in order to take advantage of purge and trap improvements. Thus, method parameters can be modified in order to optimize purge and trap cycle times. Since the purge and trap parameters were established for these methods previously, refer to application note Drinking Water Analysis Conditions for USEPA Method 524.3 and the Newly Proposed Method 524.4, purge and trap method development was not required for this application. For this study, Helium and Nitrogen purge gases were compared utilizing the same purge volume then comparing experimental results for the linearity, precision, accuracy and overall compound response for the low level requirements set by UCMR 3.&nbsp;</p><h4><strong>Experimental&nbsp;</strong></h4><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>EST Analytical Encon Evolution purge and trap concentrator</strong></a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS autosampler </strong></a>were interfaced to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7890%2F5975"><strong>Agilent 7890/5975 GC/MS</strong></a>. The purge and trap concentrator was configured with a Vocarb 3000 (K) analytical trap. A chiller unit capable of keeping the sample vials cooled below 10°C was installed on the Centurion WS autosampler. The experimental parameters are listed in Tables 1 and 2.</p><h4><strong>Conclusion</strong></h4><p>The Encon Evolution and Centurion WS in conjunction with the Agilent 7890/5975 GC/MS performed very well using both the Helium and Nitrogen purge gases and employing SIM for compound detection. The Nitrogen and the Helium purge gases met USEPA Method 524.3 curve linearity criteria and produced comparable results for precision and accuracy at the low and mid-levels of the calibration curve. Overall, the principal difference between the two purge gases was exhibited in the compound response. When examining the overall compound response factors over the curve range, it is evident that the analytes’ responses are slightly lower with the Nitrogen purge gas as opposed to the Helium purge gas.</p><h3><strong>3. Shimadzu: Comparison of Metabolites in Rice from Different Production Areas Using GC-MS/MS</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_01000_en_9c1d7cfe70.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Metabolomics is a research method for comprehensively analyzing metabolites contained in an organism. It is used for a wide variety of fields, such as medical science and food. Because food quality is affected by many components complexly, comprehensive analysis of metabolites can help improve food development and manufacturing processes. Rice contains metabolites, such as sugars, amino acids, and fatty acids. In recent years, development of more flavorful rice has been studied.&nbsp;</p><p>This article describes simultaneous analysis of 502 metabolites and multivariate analysis of a variety of rice from different production areas. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-TQ8040+NX"><strong>GCMS-TQ8040 NX</strong></a> with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Smart+Metabolites+Database+ver.+2"><strong>Smart Metabolites Database Ver. 2</strong></a> was used for measurement. <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=LabSolutions+Insight"><strong>LabSolutions Insight </strong></a>was used for data processing, and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=eMSTAT+Solution"><strong>eMSTAT Solution</strong></a> was used for multivariate analysis. The process flow, from pretreatment to data analysis, is shown in Fig. 1.</p><h4><strong>eMSTAT Solution&nbsp;</strong></h4><p>eMSTAT Solution is statistical analysis software that enables multivariate and discriminant analysis of chromatogram data. For multivariate analysis, it can discriminate between samples, and it can search for the marker peaks that contribute to those differences. For discriminant analysis, it can create a discriminant model based on training data and use the model for discriminant analysis. Users can easily switch both modes with just a single click. Workflow of the data analysis is shown in Fig. 2.</p><h4><strong>Conclusion&nbsp;</strong></h4><p>Metabolites in same variety of rice from different production areas were analyzed, and the differences between samples were identified by multivariate analysis. Score plots were used to visualize differences between the samples, and loading plots were used to confirm the characteristic compounds. Smart Metabolites Database Ver. 2, LabSolutions Insight, and eMSTAT Solution make metabolites analysis, data processing, and multivariate analysis easy for beginner users.</p><h3><strong>4. Thermo Fisher Scientific: Automated, multi-parameter gasoline characterization using GC-VUV and ASTM D8071</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_003957_gc_vuv_trace_1610_vga_industrial_an003957_na_en_3c0a64e3b2.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Gasoline is a complex hydrocarbon blend whose composition directly impacts combustion behavior, emissions, and regulatory compliance. Accurately quantifying components such as aromatics, olefins, ethanol, and benzene is critical, but traditional ASTM methods require multiple techniques (FIA, GC-FID, GC-MS, etc.) to measure all relevant parameters. Table 1 summarizes several test methods and their respective scopes.&nbsp;</p><p>ASTM D8071 introduces a consolidated method using GC-VUV, offering improved precision, spectral resolution, and reduced operational burden. This approach is now recognized as an EPA- and CARB-approved alternative to several legacy test methods, including ASTM D1319, D5599, D5769, and D3606.</p><h4><strong>Experimental&nbsp;</strong></h4><p>Gasoline samples were analyzed on the VUV Analyzer Platform for Fuels with no sample preparation required. The VUV Analyzer consists of the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/486"><strong>Thermo Scientific™ TRACE™ 1610 gas chromatograph</strong></a> coupled to the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=3&amp;search=VGA-100"><strong>VGA-100™ spectrometer detector </strong></a>(VUV Analytics, Inc.).&nbsp;</p><p>Data are acquired and processed with the VUVision™ Software and VUV Analyze™ Software (VUV Analytics, Inc), respectively, specifically configured to run ASTM D8071.&nbsp;</p><h5><strong>Workflow overview&nbsp;</strong></h5><p>The VUV Analyzer Platform for Fuels performs gasoline PIONA class analysis using a streamlined five-step workflow:&nbsp;</p><ol><li>System validation – Verifies instrument performance using standard hydrocarbons.&nbsp;</li><li>Sample prep – No preparation required.&nbsp;</li><li>Data acquisition – Performed using VUVision Software.&nbsp;</li><li>Spectral matching – Automated deconvolution with VUV Analyze Software.&nbsp;</li><li>Quantitation – Volume % and mass % calculated with high accuracy using built-in response factors and density data.</li></ol><h4><strong>Conclusion&nbsp;</strong></h4><p>GC-VUV with ASTM D8071 enables complete hydrocarbon group and compound-level analysis of gasoline in a single method. Its ability to automate spectral deconvolution and report mass and volume percentages simplifies operations while meeting strict compliance standards. This solution not only enhances analytical accuracy and repeatability but also drastically reduces operating costs and lab complexity.&nbsp;</p><ul><li>Short analysis time with full gasoline class and compound profiling in 34 minutes&nbsp;</li><li>Faster throughput with full automation from injection to reporting&nbsp;</li><li>12× lower cost-per-analysis, due to reduced labor, no calibration standards, and consolidated workflow</li></ul>

News from LabRulezGCMS Library - Week 43, 2025

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 10th November 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you applicaton notes by <strong>Agilent Technologies, EST Analytical </strong>and <strong>Shimadzu!</strong></p><h3><strong>1. Agilent Technologies: Improved Thermal Stability Leads to Retention Time Stability and Data Accuracy for the Analysis of Pesticides</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_pesticide_gc_ms_5994_8447en_agilent_773f1f135b.pdf"><strong>Full PDF for download</strong></a></li></ul><p>The analysis of trace-level pesticides is required by many governmental regulatory authorities at varying concentrations and can include hundreds of target analytes. As many of the matrices tested are complex and the analytes active, a robust and inert gas chromatography method is required.<sup>1</sup> Heavy matrices can be difficult for analytical gas chromatography columns, and higher temperatures may be required to elute the matrix off of the column. To avoid damage from high temperatures and heavy matrix, a thermally stable and ultra inert analytical column phase is needed to successfully perform this analysis. The Agilent J&amp;W 5Q series of gas chromatography columns provide the most thermally stable column available and offer inertness for difficult analytes.<sup>2</sup> The increased thermal stability not only dramatically reduces column bleed but also allows for less spectral interference at higher temperatures, leading to less need for background subtraction when searching analyte spectra against commercially available libraries.&nbsp;</p><p>While column bleed is a normal phenomenon, the increase of the baseline due to column bleed is an indication of the column phase breaking down and leading to retention time shifts. Retention time shifting can be especially difficult with the analysis of pesticides, since sensitive detectors such as mass spectrometers and triple quadrupole systems collected in selected ion mode (SIM) or multiple reaction monitoring (MRM) mode are required to achieve lower limits of detection. In both SIM and MRM collection methods, time segment windows are stated for analytes of interest, and if a retention time shifts earlier, it can move out of the collection window and require time to update the analytical collection method. By using a GC column with increased thermal stability, such as the Agilent J&amp;W DB-5Q or the Agilent J&amp;W HP-5Q, the column will be more robust to thermal and matrix damage. These columns will also maintain consistent retention times over long periods of analytical stress.&nbsp;</p><p>Retention time locking is a useful tool in the analysis of pesticides, as it can adjust column flow or pressure to normalize retention times, so that the retention times of the analytes are the same from system to system or column to column.<sup>3,4</sup> When columns with identical selectivity are interchanged, after a single injection of a test mix, the analysis can be relocked and the column flow adjusted, based on the initial calibration, to be identical as in the original method. This eliminates the need to constantly update retention times in analytical methods for SIM or MRM windows or data processing methods when replacing analytical columns.&nbsp;</p><p>When analyzing pesticides in heavy matrix, a guard column can serve two additional benefits. The guard column can help protect the analytical column from heavy matrix damage and can improve solvent and sample focusing. It is recommended to use nonpolar solvents when working with nonpolar column phases, such as the DB-5Q and HP-5Q columns. Recently it has become more common to prepare heavy matrices for pesticide analysis using QuEChERs-type preparations, with a final solvent of acetonitrile. Solvent-column phase polarity mismatch can lead to improper solvent focusing and wettability leading to improper peak shape, especially when working with columns that have low free silanol content on the deactivated surface of the fused silica. Use of a guard column can help to refocus the solvent and analytes to maintain proper peak shape.<sup>5</sup>&nbsp;</p><p>The Agilent 7010D GC/TQ uses the new Agilent High Efficiency Source (HES) 2.0 equipped with a novel dipolar RF lens that redirects carrier gas and low mass ions by &gt;&nbsp;95%, helping to reduce noise and extend instrument robustness while maintaining sensitivity.<sup>6</sup> When using DB-5Q and HP‑5Q columns in conjunction with the HES 2.0, it is possible to increase the overall robustness of the workflow for the analysis of pesticides over a wide dynamic range of analyte&nbsp;concentrations.&nbsp;</p><h4><strong>Experimental&nbsp;</strong></h4><p>An <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890"><strong>Agilent 8890 GC</strong></a> coupled with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977B"><strong>Agilent 5977B GC/MSD</strong></a> with an Inert Extractor Source was used for acquisition of data and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=MassHunter+10.0+Qualitative+Analysis"><strong>MassHunter 10.0 Qualitative Analysis software</strong></a> was used for data analysis. NIST20 library was used to confirm peak identification. A retention gap of one meter was used as a guard column to help protect the analytical column from heavy matrix and to aid in solvent focusing.</p><h4><strong>Results and discussion&nbsp;</strong></h4><p>The analysis of pesticides requires retention time stability as well as consistency from analytical column to analytical column. To compare the analytical performance of an Agilent J&amp;W DB-5Q to an Agilent J&amp;W DB-5ms UI GC column for the analysis of pesticides, a standard was first analyzed on a DB-5ms UI and the retention time locked for chlorpyrifosmethyl. The DB-5ms UI column was then replaced with a DB-5Q, and once the column was conditioned, the representative pesticide mix was again analyzed and relocked to the appropriate retention time for chlorpyrifos-methyl and analyzed again. Figure 1 demonstrates the identical selectivity of the DB-5ms UI to the DB-5Q phases and the ability to relock an existing analytical method when upgrading columns and compatibility with existing retention time locking libraries.&nbsp;</p><p>Additionally, when comparing the baseline of the DB-5Q to the DB-5ms UI column at the upper temperature limit of the chromatographic method, the increased thermal stability of the DB-5Q allows for a significant decrease in column bleed at upper temperature limits (Figure 1).</p><h4><strong>Conclusion&nbsp;</strong></h4><p>This application note demonstrated that the Agilent J&amp;W DB-5Q column has identical selectivity to the Agilent J&amp;W DB-5ms UI column, allowing for seamless adoption and use with existing retention time locking methods. The robust DB-5Q column phase maintained retention time stability even when analyzing heavy matrices and temperature cycling. The increased thermal stability not only decreased the baseline at higher temperatures but also allowed for less spectral interference and high library match factor scores. The analytical performance of the Agilent J&amp;W DB-5Q column coupled with the Agilent 7010D with the HES 2.0 ion source allows for optimal sensitivity and wide dynamic range of pesticide compounds.</p><h3><strong>2. EST Analytical: Automated Sampling of Methanol Extractions</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Purge_and_Trap_Automated_Sampling_of_Methanol_Extractions_f521577cc4.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Environmental labs are required to perform methanol extractions on highly contaminated solid waste samples. Additionally, these extractions are used for difficult matrices, for example oily waste samples, that are also soluble in methanol. Due to the variety of matrices that can be extracted with methanol there are assorted hurdles to cross in order to automate the sampling process. One of these obstacles is how the matrix can absorb the extraction solvent. For example, many soil samples require more methanol; due to the soil expanding with the solvent addition. Adding more methanol aids in rectifying this issue however, when automating sampling, the added methanol coupled with the soil expansion needs to be accommodated. For this reason, EST Analytical created software for the Centurion WS that allows the user to program the needle depth to different distances. In doing this, laboratories are able to sample soils at higher depths in order to adjust for sample absorption and at lower depths for samples that do not require the added solvent. In order to test volatile compounds in methanol extractions, a portion of the extract needs to be sampled from the vial, diluted, and purged on a purge and trap concentrator. This examination will look at the automated sampling of three different soil matrices.&nbsp;</p><h4><strong>Experimental:&nbsp;</strong></h4><p>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159"><strong>Centurion WS autosampler</strong></a> with the syringe option and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"><strong>Evolution purge and trap concentrator</strong></a> were set up to run methanol extractions. Since this is a volatile analysis, a Vocarb 3000 (K) trap was used for the analytical trap. The sampling system was configured to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1-10&amp;search=7890A"><strong>Agilent 7890A Gas Chromatograph (GC)</strong></a> and an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1-10&amp;search=5975C"><strong>Agilent 5975C inert XL Mass Spectrometer (MS)</strong></a>. The column selected for this analysis was a Restek Rxi®-624 Sil MS, with dimensions of 30m x 0.25mm I.D. x 1.4µm film thickness. Experimental parameters used for this analysis are listed in Tables 1 and 2.</p><h4><strong>Conclusions:&nbsp;</strong></h4><p>The system produced excellent results. The curve and the compound response factors met all of the method requirements. The overall precision was less than 5% RSD while the system showed an average recovery of 94%. When examining the expected analyte concentration to the extracted sand results, it was found that the average recovery was approximately 102%. Thus, the automated extraction performed extremely well. When comparing the three different matrices it was found that they all displayed similar recoveries, however the sand matrix did perform the best of the three as expected since sand tends not to absorb analytes as readily as other matrices. Finally, the ability to control the needle depth on extraction samples was a great benefit for the different matrices as the system exhibited no issues with needle clogging due to the higher needle depth when performing the potting soil extractions. As demonstrated from this study, the Centurion WS automated extraction capability would be an asset to any lab performing extractions.</p><h3><strong>3. Shimadzu: Fatty Acid Analysis of Edible Oils by GC</strong></h3><p><strong>Comparing Helium and Hydrogen as Carrier Gases</strong></p><p><strong>Comparing Analysis by GC with a Simple Screening Analysis by LC-MS</strong></p><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00852_en_e928ab40ea.pdf"><strong>Full PDF for download</strong></a></li></ul><p>There are a variety of edible oils that are sold commercially for a range of uses. They are almost entirely composed of compounds called triacylglycerols (neutral lipids), which consist of three fatty acids bound to a glycerol molecule. Because fatty acids affect the functional characteristics of food, determining the fatty acid composition of food is an important area of analysis. In this Application News, the Brevis GC-2050 (GC-FID) is used to determine the fatty acid composition of commercially available edible oils, and the use of hydrogen as a carrier gas is examined and compared with helium. This Application News also analyzes the same edible oils analyzed by LC-MS in a previous Application News1) and comparesthe results.</p><h4><strong>Equipment&nbsp;</strong></h4><p>GC-FID analysis was performed using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050"><strong>Brevis GC-2050</strong></a> gas chromatograph (Fig.1) , which is designed to be highly compact, with an installation footprint 35 % smaller than the previous model. The Brevis GC-2050 is also equipped with a carrier gas saving mode that reduces carrier gas consumption. The carrier gas saving mode reduced the use of helium carrier gas by around 89 % and hydrogen carrier gas by around 79 % in the analyses described in this article. Hydrogen carrier gas also reduced analysis times by around 25 %.</p><h4><strong>Results from Real-World Sample Analysis&nbsp;</strong></h4><p>Edible oils were derivatized and analyzed using both helium and hydrogen carrier gases. Peaks that could not be identified with the calibration standard (37 FAME mixture) were analyzed by GC-MS to determine their carbon number and degree of unsaturation. (Labeled as isomer.) Fig. 4 shows the chromatograms (partial) obtained from analyzing linseed oil with helium and hydrogen carrier gases. Similar separation was achieved with both gases.</p><h4><strong>Comparing GC-FID and FIA-MS&nbsp;</strong></h4><p>Tables 5 and 6 compare the results of analyzing eight vegetable oils for fatty acids by FIA-MS (screening analysis) and GC-FID (a helium carrier). The results reveal characteristic features of the vegetable oils, such as the most abundant fatty acids, and that coconut oil contains fatty acids with relatively low carbon numbers. More information about the screening analysis performed with a single quadrupole mass spectrometer can be found in Shimadzu Application News 01-00674-EN. <sup>1)</sup></p><h4><strong>Conclusion&nbsp;</strong></h4><p>In this Application News, the Brevis GC-2050 was used to determine the fatty acid composition of edible oils. Fatty acid analysis is typically performed using helium as the carrier gas, but in this study, hydrogen was used. This reduced analysis times while producing results that compared favorably with helium. Given the current supply issues associated with helium, hydrogen should be considered as an alternative to helium.&nbsp;</p><p>The results also show that fatty acid compositions determined by FIA-MS correlate well with results obtained by GC-FID. And because the sample pretreatment only requires sample dilution, analysis by FIA-MS is rapid, taking just 1 minute. Therefore, FIAMS seems particularly well-suited to the screening of large numbers of samples or when there is an urgent need to verify quality or safety</p>

News from LabRulezGCMS Library - Week 46, 2025

Article

Product

Events

Webinars

Application

Academy

Video

Poster

Scientists

Plastics

Environment

Food

Water

Health

Presentation

Scientific article

Interview

Toxicology

Popularization

Science and research

Software

Covid-19

Career

Laboratories

Various

Zaměření

Type of News

Focus

Everything from the world of analytical chemistry in one place. We connect people in solving their problems. At Labrulez you will find all the necessary information easily, quickly and clearly. Stop searching and start finding.

News from LabRulezGCMS Library - Week 46, 2025

News from LabRulezGCMS Library - Week 43, 2025

News from LabRulezGCMS Library - Week 42, 2025

News from LabRulezGCMS Library - Week 40, 2025

News from LabRulezGCMS Library - Week 39, 2025

News from LabRulezGCMS Library - Week 38, 2025

News from LabRulezGCMS Library - Week 36, 2025

Fingerprinting of Peach During the Ripening Process Using an Analytical Platform with Spectrometric and Volatilome-Based Chromatographic Techniques

News from LabRulezGCMS Library - Week 35, 2025

News from LabRulezGCMS Library - Week 34, 2025

Upcoming events

Pittcon 2026

57th annual conference of the DGMS & ICP-MS User´s Meeting

Eurachem Laboratory Accreditation Training Workshop

Webinars

The PFAS measurement crisis: A roundtable discussion

Cracking the toughest food matrices with advanced GC column technology

Mud Logging and Natural Gas Solutions for Micro-GC