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!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you poster by Agilent Technologies / ASMS and application notes by EST Analytical and Shimadzu!<h3>1. Agilent Technologies / ASMS: Analysis of Phthalates Using GC/MS With Hydrogen Carrier Gas: The Importance of Reducing Interferences and Contamination&nbsp;</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">Full PDF for download</a></li></ul>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.<h4>Experimental</h4><ul><li>GC: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+gc">Agilent 8890 GC</a> with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7693A">Agilent 7693A automatic liquid sampler</a> and tray</li><li>Column: Agilent HP-5MS UI 20 m x 0.18 mm id x 0.18 µm (p/n 19091S-577UI)</li><li>MSD: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977C+GC%2FMSD">Agilent 5977C Inert Plus GC/MSD</a></li></ul><h4>Conclusions</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>2. EST Analytical: The Determination of Flavors in E-Liquids Using Purge and Trap Concentration</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">Full PDF for download</a></li></ul>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.<h4>Experimental</h4>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">Evolution purge and trap concentrator </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">Centurion WS syringe autosampler</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.<h4>Conclusions</h4>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.<h3>3. Shimadzu: Determination of Nitrobenzene Compounds in Nifedipine by GCMS&nbsp;</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">Full PDF for download</a></li></ul><h4>User Benefits</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>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">Shimadzu GCMSQP2050</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.<h4>Analytical Conditions</h4>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">GCMS-QP2050</a> system was used for this Application News.<h4>Conclusion&nbsp;</h4>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.

News from LabRulezGCMS Library - Week 36, 2025

Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 8th September 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you poster by Agilent Technologies / ASMS and application notes by EST Analytical and Shimadzu!<h3>1. Agilent Technologies / ASMS: Optimizing the Efficiency and Productivity of GC/MS Workflows to Improve Laboratory Sustainability</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_db_5q_hydroinert_sustainability_asms_2025_mp_365_en_agilent_3cc1d968a1.pdf">Full PDF for download</a></li></ul>Today, laboratories consume a staggering 10 times more energy and water than a typical office [1]. Labs with GC and GC/MS systems have unique sustainability challenges due to the resource-intensive nature of these instruments. They consume large amounts of gas and energy while also generating hazardous waste products. According to Agilent customer surveys, 85 percent of labs and organizations have sustainability goals in place, and 83 percent of lab leaders believe their current workflow requires optimization to meet their sustainability ambitions [2]. A more efficient laboratory is a more sustainable one. This poster outlines some simple approaches that laboratories can take, today, to optimize workflow efficiency and productivity, thus minimizing resource consumption.<h4>Experimental</h4>Laboratory workflows are the cornerstone of laboratory operations. In this poster we will illustrate the impact of column scaling for GC/MS workflows, the use of hydrogen as an alternative, renewable carrier gas for GC and GC/MS. Hydrogen offers unique safety and reactivity challenges that we will address with Agilent HydroInert source. Lastly, we will demonstrate simple and effective ways to conserve gases, focusing on existing helium carrier gas workflows. In the end, these simple, easy-toimplement practices will illustrate how sustainability can be accomplished in conjunction with improving workflow profitability and productivity.<h4>Alternative Carrier Gases</h4><h5>Carrier Gases&nbsp;</h5>Helium shortages have impacted analytical laboratories since 2006 and repeatedly been in short supply[3]. While helium’s availability has improved in recent years, there are still concerns surrounding supply stability and rising costs. Knowing the cyclic nature of the helium supply chain, exploring alternative carrier gas options like hydrogen and nitrogen are necessary for laboratory managers looking for sustainability, flexibility, and cost savings measures. Specifically, hydrogen carrier gas is a good option for GC/MS methods and when using the Agilent Method Translator tool, methods can easily be transferred. Figure 3 highlights parameter adjustments for translation like pressure, flow, velocity, and temperature program rates to ensure similar relative retention orders with the alternative gas. Hydrogen when compared to nitrogen as a carrier gas provides the best alternative for chromatographic resolution and speed. Figure 4 demonstrates a method transfer of helium to hydrogen carrier gas for ASTM D5769.<h4>Consumables Impact&nbsp;</h4><h5>Tailored <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=19&amp;mainauthorItems=10">GC Columns&nbsp;</a></h5>Consumables in GC/MS workflows are often overlooked as contributing factors to sustainability and optimization. For example, minimizing column bleed and improving GC column thermal durability can have a major beneficial impacted for both data quality and instrument uptime. <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=19&amp;mainauthorItems=10&amp;search=J%26W+5Q">Agilent J&amp;W 5Q GC columns</a> provide the lowest bleed standard for GC/MS workflows. This provides less downtime from ion source cleaning, faster conditioning, and minimize reruns due to data quality issues. Figure 5 and 6 highlight thermal stability and sensitivity of the DB-5Q and HP-5Q columns.<h4>Conclusions</h4>Optimizing the efficiency and productivity of GC/MS workflows are critical for analytical laboratories to stay competitive and profitable. This poster demonstrated a time savings of 50% with column scaling from a conventional GC/MS column to a high-efficiency column, successful alternative carrier gas method transfer, reducing potential source reactivity when using hydrogen carrier, and demonstrated 3.8 to 7X factor reduction of carrier gas consumption when using software features and the Helium Conservation module.<h3>2. EST Analytical: Drinking Water Analysis Conditions for USEPA Method 524.3 and the Newly Proposed Method 524.4</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_Drinking_Water_Analysis_Conditions_for_USEPA_Method_524_3_and_524_4_Agilent_315971a468.pdf">Full PDF for download</a></li></ul>In June 2009, the United States Environmental Protection Agency (USEPA) promulgated a new drinking water method, 524.3. Due to advances in analytical instrumentation, Method 524.3 allows laboratories to modify purge and trap and GCMS conditions. Currently the USEPA is investigating the option of using Nitrogen as the purge gas in a new drinking water method, 524.4. This application note will explore purge and trap conditions for both Helium and Nitrogen purge gases.<h4>Discussion: &nbsp;</h4>When the USEPA published Method 524.3, they allowed some method flexibility. However, the method still required Helium as the purge gas. Due to fluctuations in the price and availability of high purity Helium, the USEPA has drafted Method 524.4 which would allow for high purity Nitrogen to be used for the purge gas.&nbsp;Method 524.4 provides the same flexibility as Method 524.3, thus method parameters can be modified in order to optimize purge and trap cycle times. Although the new method allows for a shorter desorb time, moisture build up can still be a problem as the new preservation scheme causes effervescing in the sparge vessel. EST has two features that can aid in moisture control and the “foaming” caused by the effervescing. First, EST has a foam sensor to detect any issues with foaming. The foam sensor for the Encon Evolution has a unique placement above the bulb of the sparge vessel, thus allowing the bulb to control the effervescing bubbles and not sending a false positive signal to the software causing the sample sequence to be aborted. Secondly, the Encon Evolution utilizes an 8 port valve instead of a 6 port valve. This unique engineering has the advantage of excluding the Moisture Reduction Trap (MoRT) from the desorb pathway thus aiding in moisture control for the system. Furthermore, the Centurion WS has the ability of taking samples from the vials without moving the samples. This eliminates opportunities for vial movement errors that would negatively impact productivity.<h4>Experimental:&nbsp;</h4>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Encon Evolution purge and trap concentrator</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS Autosampler </a>were interfaced to a GC/MSD. 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.<h4>Conclusion:&nbsp;</h4>The Encon Evolution and Centurion WS performed very well using both the Helium and Nitrogen purge gases and the 440ml and 390ml purge volumes. The Nitrogen and the Helium purge gases met USEPA method 524.3 criteria. Furthermore, the 440ml purge volume and the 390ml purge volume produced comparable results. 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.<h3>3. Shimadzu: Ultra-Sensitive Analysis of β-cyclocitral in Water Using Solid Phase Micro Extraction and Gas Chromatography–Mass Spectrometry</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_09_ssk_022_en_c7d7b3ef8a.pdf">Full PDF for download</a></li></ul><h4>User Benefits</h4><ul><li>SPME-GC-MS supports effective monitoring of water environments</li><li>Excellent sensitivity, achieving quantification of β-cyclocitral in water within the ultra-trace level</li><li>SPME provides a solvent-free extraction, efficient, and highly sensitive method for detecting β-cyclocitral&nbsp;</li></ul>Cyanobacterial blooms, commonly known as algal blooms, cause rivers and lakes to turn vividly green due to the excessive growth of cyanobacteria. This phenomenon is caused by factors such as global population growth, industrial pollution, and rising water temperatures caused by climate change. 1)Cyanobacterial blooms produce volatile organic compounds (VOCs) like β-cyclocitral and β-ionone, which cause unpleasant odors and reduce the quality of drinking water and aquatic products. This leads to consumer complaints and economic lossesin aquaculture and water treatment.&nbsp;Detecting and quantifying β-cyclocitral (Figure. 1) at trace levels is therefor essential for effective water management. However, conventional solvent extraction methods often fail to detect βcyclocitral, as it requires acidification or heating to be effectively released from the matrix. 2)&nbsp;In contrast, solid phase microextraction (SPME) enables efficient detection by facilitating the thermal desorption of β-cyclocitral from sample matrices onto the fiber. Moreover, SPME reduces solvent use and shortens sample preparation time compared to traditional extraction techniques, making it a suitable approach for the analysis of thermally induced volatile compounds like βcyclocitral.&nbsp;This application news describes the suitability of β-cyclocitral analysis using SPME automatic injection (<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-6000+Plus">AOCTM-6000 Plus</a>) and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2020+NX">GCMS-QP2020 NX</a> of Shimadzu. The developed method enables highly sensitive quantitation of β-cyclocitral, achieving detection at the pg/mL level.<h4>Analytical Conditions</h4>β-cyclocitral in water was analyzed using <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2020+NX">GCMS-QP2020 NX</a> of Shimadzu equipped with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-6000+Plus">AOC-6000 Plus autosampler</a> as shown in Figure 2. The detailed analytical conditions of instrument was provided in Table 1. For the SPME analysis, 50/30 μm DVB/CAR/PDMS fiber was used, and SH-PolarWax (30 m × 0.25 mm I.D., 0.25 μm) was used as the analytical column. The AOC-6000 Plus supports various injection techniques, including liquid injection, headspace (HS) injection, and solidphase microextraction (SPME) injection. Furthermore, sample preparation and preprocessing in the AOC-6000 Plus are automatically carried out during injection into the GC system, improving efficiency and reproducibility.<h4>Conclusions&nbsp;</h4>In this application news, SPME-GC-MS method was developed and validated for the ultra-sensitive quantitation of β-cyclocitral in water using the Shimadzu GCMS-QP2020 NX coupled with the AOC-6000 Plus. The method demonstrated quantification capability down to the picogram-per-milliliter (pg/mL) level, excellent linearity (R² &gt; 0.999). Accuracy and precision were confirmed with a recovery of 105.3% and %RSD of 0.7. These results confirm the reliability and suitability of the SPME-GC-MS method for ultra-trace quantification of β-cyclocitral in environmental watersamples.

News from LabRulezGCMS Library - Week 37, 2025

<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=45&amp;search=USEPA+Method+524.2">USEPA Method 524.2</a> 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. 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.&nbsp;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.<h4>Experimental:&nbsp;</h4>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Evolution purge and trap concentrator</a> and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS autosampler</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?mainauthorItems=10&amp;search=7890A">Agilent 7890A GC</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5975C">5975C inert XL MS</a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=7&amp;search=Restek+Rxi-624+Sil+MS">Restek Rxi-624 Sil MS</a> 30m x 0.25mm x 1.4µm column. The purge and trap and GC/MS parameters used for this study are listed below.<h5>Purge and Trap Parameters</h5><ul><li>Concentrator: EST Evolution</li><li>Trap type: Vocarb 3000</li><li>Valve oven temperature: 130 °C</li><li>Transfer line temperature: 130 °C</li><li>Trap temperature: 35 °C</li><li>Moisture Reduction Trap (MoRT) temperature: 39 °C</li><li>Purge time: 11 min</li><li>Purge flow: 40 mL/min</li><li>Dry purge Temp.: Ambient</li><li>Dry Purge Flow: 40mL/min</li><li>Dry Purge Time: 1.0 min &nbsp;</li><li>Desorb pressure Control: ON</li><li>Desorb Pressure: 5psi</li><li>Desorb time: 4 min</li><li>Desorb preheat delay: 15 sec</li><li>Desorb temperature: 250 °C</li><li>MoRT bake temperature: 210 °C</li><li>Bake temperature: 260 °C</li><li>Sparge vessel bake temperature: 110 °C</li><li>Bake time: 6 min</li><li>Bake flow: 70 mL/min</li></ul><h5>Auto-Sampler (EST Centurion WS):</h5><ul><li>Sample type: Water</li><li>Water volume: 25 mL</li><li>Internal standard volume: 5 µL</li></ul><h5>GC/MS Parameters</h5><ul><li>System: Agilent 7890A GC / 5975C inert XL MS</li><li>Inlet: Split mode, 220 °C, 40:1 split ratio, 12.153 psi head pressure</li><li>Column: Restek Rxi-624Sil MS, 30 m × 0.25 mm × 1.4 µm</li><li>Oven program: 45 °C (1 min) → ramp 15 °C/min → 220 °C, hold 1.33 min (total run ~14 min)</li><li>Column flow rate: 1 mL/min helium</li><li>Total flow: 44 mL/min</li><li>Source temperature: 230 °C</li><li>Quadrupole temperature: 150 °C</li><li>Transfer line temperature: 180 °C</li><li>Scan range: m/z 35–300, 5.2 scans/sec</li><li>Solvent delay: 0.7 min</li></ul>A calibration curve was established with a linear range of 0.25 to 40µg/L using the USEPA Method 524.2 standards from Restek. After the curve was determined, method detection limits were ascertained by running a series of seven replicate 0.25 µg/L standards and calculated using the procedure outlined in 40 CFR Part 136 Appendix B. Finally, seven 20 µg/L standards were examined in order to verify the precision and accuracy of the analysis. The results of this study are displayed in Tables 1 and 2 while Figure 1 presents a 20 µg/L standard GC/MS chromatogram.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Table_3_Compound_Linearity_and_Response_Factor_Table_f63b77844f.jpg" alt="EST Analytical: Table 1 - Compound Linearity and Response Factor Table" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Table_3_Compound_Linearity_and_Response_Factor_Table_f63b77844f.jpg 153w," sizes="100vw" width="1104" height="1126"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Table_4_MDL_and_Precision_and_Percent_Recovery_Table_27572600f0.jpg" alt="EST Analytical: Table 2 - MDL and Precision and Percent Recovery Table" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Table_4_MDL_and_Precision_and_Percent_Recovery_Table_27572600f0.jpg 186w," sizes="100vw" width="1358" height="1143"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Figure_1_20mg_L_Standard_Chromatogram_7ff795984b.jpg" alt="EST Analytical: Figure 1 - 20 µg/L Standard Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Figure_1_20mg_L_Standard_Chromatogram_7ff795984b.jpg 245w," sizes="100vw" width="1431" height="789"><h4>Conclusions:&nbsp;</h4>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.

USEPA 524.2 Method Validation Using the Evolution Purge and Trap Concentrator and the Centurion WS Autosampler

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!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you posters by Agilent Technologies / ASMS, Shimadzu / ASMS and application note by EST Analytical!<h3>1. Agilent Technologies / ASMS: Beyond Aligners: Unmasking Hidden Extractables and Leachables in Orthodontic Devices</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">Full PDF for download</a></li></ul>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.<h4>Experimental</h4><h5>Sample Analysis&nbsp;</h5>Samples were analyzed using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7250">Agilent 7250 accurate mass GC-qTOF</a> equipped with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC">8890 GC</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;<h5>Data Analysis&nbsp;</h5>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.<h4>Conclusions</h4>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;<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>2. EST Analytical: Optimization of 1,4-Dioxane and Ethanol Detection Using USEPA Method 8260</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">Full PDF for download</a></li></ul>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;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;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.<h4>Experimental</h4>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Evolution concentrator</a> affixed with a Vocarb 3000 trap. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS autosampler</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">Agilent 7890A Gas Chromatograph (GC)</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C">5975C inert XL Mass Spectrometer (MS)</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">Restek Rxi-624 Sil MS</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.<h4>Conclusions</h4>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.<h3>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</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">Full PDF for download</a></li></ul>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;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.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;<h4>Materials and methods&nbsp;</h4>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">GCMS-TQ8050 NX</a> equipped with headspace sampler <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=HS-20+NX">HS-20 NX </a>(Trap) (Figure 1), manufactured by Shimadzu Corporation Japan, was used to quantify impurities in the PEG 3350 sample<h4>Conclusion</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

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!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you application notes by Agilent Technologies, EST Analytical, Shimadzu and Thermo Fisher Scientific!<h3>1. Agilent Technologies: A Chemometric Approach for Ambient Air Monitoring Using Thermal Desorption GC/MS</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">Full PDF for download</a></li></ul>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;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.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">Markes TD100-xr automated thermal desorber</a> (Figure 2) and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+gc">Agilent 8890 GC system</a> with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977c">5977C GC/MSD</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.<h4>Conclusion&nbsp;</h4>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;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.<h3>2. EST Analytical: USEPA 524.2 Method Validation Using the Evolution Purge and Trap Concentrator and the Centurion WS Autosampler</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">Full PDF for download</a></li></ul>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;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.<h4>Experimental</h4>The sampling system used for this study was the<a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160"> EST Analytical Evolution purge and trap concentrator </a>and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS autosampler</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">Agilent 7890A GC</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C">5975C inert XL MS</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">Restek Rxi-624 Sil</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.<h4>Conclusions</h4>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.<h3>3. Shimadzu: Dual-Column Analysis of Blood AlcoholContent (BAC) Using Nitrogen Carrier Gas with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050">Brevis GC-2050</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">Full PDF for download</a></li></ul>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;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;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">Nexis GC-2030</a>, Shimadzu also offers the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050">Brevis GC-2050</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">HS-20 NX headspace sampler </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.<h4>Separation of 10 Blood VOCs&nbsp;</h4>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.<h4>Conclusion&nbsp;</h4>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.<h3>4. Thermo Fisher Scientific: Routine analysis of 7N high purity gallium phosphide by Glow Discharge Mass Spectrometry</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">Full PDF for download</a></li></ul>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 electronics1-5. GaP wafers offer several advances over traditional silicon wafers, including high efficiency, high-speed operation, and highpower handling capabilities4-5.&nbsp;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">Element GD PLUS GD Mass Spectrometer</a>.&nbsp;<h4>Experiment&nbsp;</h4>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;<h4>Method development&nbsp;</h4>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.<h4>Conclusions&nbsp;</h4>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;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.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;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.

News from LabRulezGCMS Library - Week 39, 2025

<h4>Abstract&nbsp;</h4>Before the advent of orange juice from concentrate, people would fresh squeeze oranges for their juice. Concentrate helped make orange juice easier to make and increased its popularity. Following concentrate, manufacturers used flash pasteurization and created ready to drink orange juice and again sales increased. Due to disease in the orange groves and the possibility of the crops getting destroyed by frost, the production of orange juice has gotten more expensive. The increase in production costs creates competition within the orange juice industry to create an orange juice that the public will enjoy and increase their consumption. This application will look at the flavor compound abundances of three different brands of orange juice using purge and trap concentration.&nbsp;<h4>Introduction</h4>Pasteurization is the first step in the creation of commercial orange juice. This is required in order to kill any harmful bacteria in the juice before it is sold. After the juice is pasteurized, it can be sold. However, since different orange varieties are in season at different times, most juice is squeezed and stored. The storage times vary and with storage there can be other issues. One of these issues is oxidation. Thus, many companies remove the oxygen from the juice before they store it. Between pasteurization and oxygen removal, the juice will lose some of its flavor. This is where juice manufacturers can differentiate themselves.&nbsp;Flavor compounds and amounts can make a substantial difference in the overall taste, acidity and odor of the juice. So, to create a juice that the public wants to buy, it is essential that the analysis of the flavor compounds and the percentage of these flavors be accounted for. Purge and trap is an excellent technique for the extraction of volatile flavor compounds within a liquid matrix. This is an exhaustive technique and generates reproducible results. This application will compare the reproducibility and ratios of flavor compounds in orange juice using the EST Analytical Evolution purge and trap concentrator.&nbsp;<h4>Experimental</h4>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Evolution purge and trap concentrator </a>was set up with a Vocarb™ 3000 trap while the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS autosampler</a> was set to run in soil mode. The sampling system was configured to an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7890A">Agilent 7890A Gas Chromatograph (GC)</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5975C">5975C inert XL Mass Spectrometer (MS) </a>for separation and analysis. As the compounds of interest for this analysis were volatile, a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=7&amp;search=Restek+Rxi-624+Sil+MS">Restek Rxi® 624 Sil MS</a> 30m X 0.25mm X 1.4µm column was affixed in the GC. Sampling and analysis parameters were optimized and are listed below.<h5>Purge and Trap Parameters</h5><ul><li>Concentrator: EST Encon Evolution</li><li>Trap type: Vocarb 3000</li><li>Valve oven temperature: 150 °C</li><li>Transfer line temperature: 150 °C</li><li>Trap temperature: 35 °C</li><li>Moisture Reduction Trap (MoRT) temperature: 39 °C</li><li>Purge time: 11 min</li><li>Purge flow: 40 mL/min</li><li>Dry purge Temp.: Ambient</li><li>Dry Purge Flow: 40mL/min</li><li>Dry Purge Time: 1.0 min &nbsp;</li><li>Desorb pressure Control: ON</li><li>Desorb Pressure: 6psi</li><li>Desorb time: 0.5 min</li><li>Desorb preheat delay: 5 sec</li><li>Desorb temperature: 260 °C</li><li>MoRT bake temperature: 210 °C</li><li>Bake temperature: 270 °C</li><li>Sparge vessel bake temperature: 120 °C</li><li>Bake time: 8 min</li><li>Bake flow: 85 mL/min</li></ul><h5>Auto-Sampler (EST Centurion WS):</h5><ul><li>Sample type: Soil</li><li>Sample Fill Mode: Syringe</li><li>Water Heater Temp.: 85°C</li><li>Sample Preheat Time: 0.5min</li><li>Sample Preheat Temp.: 40°C</li><li>Soil Valve Temp.: 85°C</li><li>Soil Transfer Line Temp.: 150°C</li><li>Minimizer Time: 2 min</li></ul><h5>GC/MS Parameters</h5><ul><li>System: Agilent 7890/5975C</li><li>Inlet: Split mode, 220 °C, 40:1 split ratio, 12.153 psi head pressure</li><li>Liner: Restek Split liner, 1mm x 6.3 x 78.5</li><li>Column: Restek Rxi-624Sil MS, 30 m × 0.25 mm × 1.4 µm</li><li>Oven program: 45 °C (1 min) → ramp 15 °C/min → 300 °C, hold 5.00 min (total run ~23 min)</li><li>Column flow rate: 1 mL/min helium</li><li>Total flow: 44 mL/min</li><li>Source temperature: 230 °C</li><li>Quadrupole temperature: 150 °C</li><li>Transfer line temperature: 180 °C</li><li>Scan range: m/z 30–350, 4.4 scans/sec</li><li>Solvent delay: 0.7 min</li></ul>Three&nbsp;different&nbsp;orange&nbsp;juice&nbsp;brands&nbsp;were&nbsp;purchased&nbsp;at&nbsp;the&nbsp;local&nbsp;market.&nbsp;&nbsp;Ten&nbsp;milliliters&nbsp;of&nbsp;each&nbsp;orange&nbsp;juice&nbsp;was&nbsp;measured&nbsp;and&nbsp;placed&nbsp;in&nbsp;a&nbsp;40ml&nbsp;vial.&nbsp;&nbsp;Each&nbsp;vial&nbsp;was&nbsp;then&nbsp;deposited&nbsp;in&nbsp;the&nbsp;Centurion&nbsp;WS&nbsp;autosampler&nbsp;to&nbsp;be&nbsp;purged&nbsp;in&nbsp;soil&nbsp;mode&nbsp;and&nbsp;concentrated&nbsp;on&nbsp;a&nbsp;Vocarb&nbsp;3000&nbsp;trap&nbsp;in&nbsp;the&nbsp;Evolution&nbsp;concentrator.&nbsp;Finally,&nbsp;the&nbsp;samples&nbsp;were&nbsp;in&nbsp;run&nbsp;in&nbsp;triplicate&nbsp;in&nbsp;order&nbsp;to&nbsp;ensure&nbsp;the&nbsp;reproducibility&nbsp;of&nbsp;the&nbsp;results.&nbsp;&nbsp;Agilent&nbsp;MassHunter&nbsp;Qualitative&nbsp;Analysis&nbsp;software&nbsp;was&nbsp;used&nbsp;for&nbsp;the&nbsp;determination&nbsp;of&nbsp;the&nbsp;flavor&nbsp;compounds&nbsp;in&nbsp;the&nbsp;juice&nbsp;samples.&nbsp;&nbsp;Table&nbsp;1&nbsp;displays&nbsp;the&nbsp;reproducibility&nbsp;of&nbsp;the&nbsp;sampling&nbsp;process&nbsp;whereas&nbsp;Table&nbsp;2&nbsp;lists&nbsp;a&nbsp;comparison&nbsp;of&nbsp;the&nbsp;flavor&nbsp;compound&nbsp;abundances.&nbsp;&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Table_1_Reproducibility_of_the_Results_fa8fd6f4be.jpg" alt="EST Analytical: Table 1 Reproducibility of the Results" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Table_1_Reproducibility_of_the_Results_fa8fd6f4be.jpg 245w," sizes="100vw" width="1199" height="754"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Table_2_Flavor_Compound_Abundance_Summary_d16be388f3.jpg" alt="EST Analytical: Table 2 Flavor Compound Abundance Summary" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Table_2_Flavor_Compound_Abundance_Summary_d16be388f3.jpg 244w," sizes="100vw" width="1197" height="767">Figure&nbsp;1&nbsp;is&nbsp;a&nbsp;bar&nbsp;graph&nbsp;comparison&nbsp;of&nbsp;the&nbsp;compounds&nbsp;in&nbsp;the&nbsp;three&nbsp;juice&nbsp;brands&nbsp;while&nbsp;Figures&nbsp;2,&nbsp;3&nbsp;and&nbsp;4&nbsp;are&nbsp;the&nbsp;respective&nbsp;chromatograms&nbsp;of&nbsp;the&nbsp;juice&nbsp;samples.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Figure_1_Bar_Graph_Compound_Abundance_Comparison_f2fd098cdf.jpg" alt="EST Analytical: Figure 1 Bar Graph Compound Abundance Comparison" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Figure_1_Bar_Graph_Compound_Abundance_Comparison_f2fd098cdf.jpg 221w," sizes="100vw" width="1342" height="950"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Figure_2_Brand_A_Chromatogram_0d5f5f8daa.jpg" alt="EST Analytical: Figure 2 Brand A Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Figure_2_Brand_A_Chromatogram_0d5f5f8daa.jpg 245w," sizes="100vw" width="1399" height="871"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Figure_3_Brand_B_Chromatogram_eefc215bd1.jpg" alt="EST Analytical: Figure 3 Brand B Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Figure_3_Brand_B_Chromatogram_eefc215bd1.jpg 245w," sizes="100vw" width="1390" height="887"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Figure_4_Brand_C_Chromatogram_07adab6c82.jpg" alt="EST Analytical: Figure 4 Brand C Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Figure_4_Brand_C_Chromatogram_07adab6c82.jpg 245w," sizes="100vw" width="1399" height="871"><h4>Conclusions</h4>Using the EST Analytical Evolution purge and trap concentrator coupled to the Centurion WS autosampler to evaluate flavor compounds in orange juice samples proved to be a reliable sampling technique. The results were reproducible and the chromatography was excellent. The three different orange juice brands had very similar chromatograms; however upon further analysis many subtle differences in the abundances of the flavor compounds could be discerned. Traditionally, headspace and solid phase micro extraction sampling are used for this type of analysis. However, the purge and trap sampling technique used for this examination offered an excellent alternative for the determination of the volatile components in a juice matrix.

Flavor Compound Abundances in Orange Juice Comparison Using Purge and Trap

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!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you application notes by Agilent Technologies and EST Analytical, poster by Shimadzu and smart note by Thermo Fisher Scientific!<h3>1. Agilent Technologies: Equimolar Response to ASTM D5623 Relevant Sulfur Compounds</h3>Using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC">Agilent 8890 gas chromatograph</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8355%C2%A0SCD">8355 sulfur chemiluminescence detector (GC/SCD)</a><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">Full PDF for download</a></li></ul>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.1 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;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;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 method2 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;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.<h4>Methods&nbsp;</h4><h5>Instrumentation&nbsp;</h5>Two <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8890+GC">Agilent 8890 GC systems</a> were equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=8355%C2%A0SCD">8355&nbsp;SCD</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">7693A automatic liquid sampler</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;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.<h4>Results and discussion</h4><h5>Use of GC/FID for solvent elution determination&nbsp;</h5>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;<h4>Conclusion&nbsp;</h4>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.<h3>2. EST Analytical: Reducing Carryover in Environmental Water Samples</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">Full PDF for download</a></li></ul>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.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.<h4>Experimental</h4>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Evolution concentrator</a> and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion WS autosampler</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">Agilent 7890A GC </a>and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=5975C">5975C inert XL MS</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">Restek Rxi-624 Sil</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.<h4>Conclusions</h4>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.<h3>3. Shimadzu / AOAC: Analysis of PFAS in juice using Head-Space Solid Phase Microextraction-Gas Chromatography/Mass Spectrometry (HS-SPME GCMS)</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">Full PDF for download</a></li></ul>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.<h4>Materials and Methods</h4>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.<h4>Conclusion&nbsp;</h4>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=GCMS-TQ8040+NX">Shimadzu GCMS-TQ8040 NX triple quadrupole instrument</a>, configured with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=3&amp;search=AOC-6000+Plus+SPME">AOC-6000 Plus SPME</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.<h3>4. Thermo Fisher Scientific: Safe use of carrier hydrogen for air monitoring with Multi-Gas TD-GC-MS</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">Full PDF for download</a></li></ul>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.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;<h4>Experimental&nbsp;</h4>In this study, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=7&amp;search=TD100-xr">Markes TD100-xr™ Multi-Gas system</a>, coupled with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/486">Thermo Scientific™ TRACE™ 1610 gas chromatograph</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/484">Thermo Scientific™ ISQ™ 7610 single quadrupole mass spectrometer,</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.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">Thermo Scientific™ Chromeleon™ Chromatography Data System (CDS)</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.<h4>Conclusion&nbsp;</h4>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;<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>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.

News from LabRulezGCMS Library - Week 40, 2025

Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 6th October 2025? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you poster by Agilent Technologies / AOAC, application notes by EST Analytical and Shimadzu and brochure by Thermo Fisher Scientific!<h3>1. Agilent Technologies / AOAC: Method Translation for the Analysis of Vanilla Extracts Using a Compact, Single Channel GC-FID and Carrier Gas Switching Module</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/ps_vanilla_single_channel_gcfid_carrier_gas_aoac_2025_w020_en_agilent_17c7d568c9.pdf">Full PDF for download</a></li></ul>Vanilla is a flavor variety that has been heavily impacted by changes in consumer habits as well as by supply and demand of vanilla beans used to produce high-quality vanilla extracts. Unfortunately, these market conditions, increase the likelihood of adulteration in vanilla extracts by use of aroma chemicals that are not naturally occurring. Common adulterants are coumarin (C), ethyl vanillin (EV), eugenol (E), and guaiacol (G).2,3 Adulteration impacts the standard of identity for vanilla extracts established by the U.S. FDA; therefore, flavor companies rely on QC labs to implement reliable and sensitive analysis techniques for screening incoming raw ingredients against expected purity standards before the ingredient can enter a flavor formula on the manufacturing floor. Screening is typically executed with gas chromatography (GC)- based methods adapted from those used in a R&amp;D lab. However, differences in column length, diameter, and phase can make it seem challenging to harmonize GC methods across the R&amp;D and QC functions within a company due to the different analysis objectives of the respective laboratories.&nbsp;<h4>Experimental Goals</h4><ul><li>Demonstrate the ease of the Agilent Method Translator in harmonizing GC methods for multiple columns and gases&nbsp;</li><li>Establish method precision, linearity, and resolution on standards of vanilla-like adulterants using the translated methods&nbsp;</li><li>Successfully showcase the method translation using store-bought extracts to verify the integrity of the fastest GC method on samples containing matrix&nbsp;</li><li>Screen for and quantify any vanilla adulterants in the samples of vanilla extracts with the goal of detecting no adulterants using the fastest GC method.</li></ul><h4>Experimental&nbsp;</h4><ul><li>GC System: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8850+GC">Agilent 8850 GC</a> with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7693A+Automatic+Liquid+Sampler">7693A Automatic Liquid Sampler</a></li></ul><h4>Conclusions</h4><h5>Method Translation</h5><ul><li>The method translator tool provided an easy conversion of a 50-minute-long method to one that is &lt; 5 minutes resulting in a speed gain of 10-fold and 14-fold, for He and H2 carrier gases, respectively (Figures 2 and 3)&nbsp;</li><li>Resolution of analytes were &gt;4 on the 60 m and &gt;3.5 on the 10 m DB-1 columns (Table 2)</li><li>Precision was &lt;1.85% RSD and &lt;2.5% RSD for He and H2 carrier, respectively (Table 3)</li><li>Linearity was demonstrated from 10 ppm to 100,000 ppm for He and H2 carrier with R2 ranging from 0.9997 to 1.0000&nbsp;</li></ul><h5>Carrier Gas Switching</h5><ul><li>He and H2 carrier gases were alternated line by line in a sequence table for increased analytical efficiency and higher throughput while demonstrating the flexibility the helium conservation module provides its users while also eliminating manual changes to plumbed gases at the GC EPC Module.</li></ul><h3>2. EST Analytical: Optimizing 8260 Sample Throughput - Solutions for the Determination of Bromomethane by Purge and Trap</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_Solutions_for_the_Determination_and_Stability_of_Bromomethane_by_P_and_T_App_Note_Rev_2_177c75d029.pdf">Full PDF for download</a></li></ul>The United States Environmental Protection Agency’s (USEPA) Method 8260 has an extensive list of compounds of interest. In order to purge and trap these analytes, there needs to be an analytical trap able to trap these compounds and desorb them to the Gas Chromatograph/Mass Spectrometer (GC/MS) both accurately and efficiently. Due to the broad range of compounds on the Method 8260 list, there are many issues to take into account. Purge efficiency, molecular weight, volatility, and water are among the most problematic issues. The purge and trap concentrator and analytical trap must be able to account for all of these concerns.&nbsp;The most commonly used analytical trap is the Vocarb® 3000 due to its ability to trap and desorb the extensive analyte list both effectively and correctly. However, the Vocarb® 3000 trap is not without its drawbacks. One of which is Bromomethane degradation in the trap over time. This application will examine the Vocarb® 3000 and a custom trap along with the optimum trap temperature parameters for the stability of Bromomethane.&nbsp;<h4>Experimental</h4>The purge and trap concentrator used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">EST Analytical Evolution</a>. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">Centurion Water and Soil autosampler</a> equipped with the syringe option was employed as the autosampler. Separation and analysis of the volatile compounds was performed by the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=1&amp;search=7890A">Agilent 7890A Gas Chromatograph (GC) </a>and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5977B">5977B Mass Spectrometer</a> (MS). 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">Restek Rxi624 Sil MS</a> 30m x 0.25mm x 1.4µm column. The purge and trap parameters and analytical traps used for this study are listed in Tables 1 and 2 while Table 3 details the GC/MS parameters.<h4>Conclusions</h4>Initially, all of the traps and heating parameters used in the EST Analytical Evolution met USEPA method 8260 requirements and could be used in the laboratory. However, the custom trap and the higher temperature desorb and bake showed a lower response when compared to using a lower temperature desorb and bake. Furthermore, over time, the custom trap and higher temperature desorb and bake displayed lower recoveries of Bromomethane which could in turn affect the continuing calibration standards. The Vocarb® 3000 trap with the lower temperature desorb and bake proved to be the optimum method for sampling USEPA Method 8260 compounds. The technique met all of the method requirements and exhibited the best response and stability not only for Bromomethane but also for the rest of the extensive compound list.<h3>3. Shimadzu: Quantitative Analysis of Furan and Alkylfurans in Processed Food Using Headspace GC-MS</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00906_en_878a49b98e.pdf">Full PDF for download</a></li></ul>Furan and alkylfurans are aromatic compounds with a fivemembered ring structure. Furan and some alkylfurans, such as 2-methylfuran, 3-methylfuran, and 2,5-methylfuran (furan with a hydrocarbon chain attached), are found in processed food. They are generated through a variety of pathways during heat treatment of the food. Some countries have studied these compounds and concluded they are a health concern. 1) At present, no country has set permissible levels for furan or alkylfurans in food. But since they are harmful substances that are generated unintentionally during the processing of food, analyzing them is becoming increasingly important. In this Application News, the levels of furan and alkylfurans in commercially available processed food were measured.<h4>Equipment&nbsp;</h4>The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050">GCMS-QP2050</a> gas chromatograph mass spectrometer has a compact design for a smaller installation footprint. When combined with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20+NX">HS-20 NX headspace sampler</a>, the GCMSQP2050 can simply and accurately measure furan and alkylfuran levels in processed food. The DuraEase ion source, which is specifically designed for durability and ease of maintenance, also providesreduced maintenance requirements.<h4>Conclusion&nbsp;</h4>In this Application News, headspace GC-MS analysis was used to measure levels of furan and alkylfurans in processed food. Analysis of standard samples produced good results in terms of separation, calibration curve linearity, and repeatability. Analyzing food samples and comparing the results obtained by the external standard method and the standard addition method showed that the matrix effects differed depending on the sample.<h3>4. Thermo Fisher Scientific: Everything You Need in a GC Detector: VGA-100 Gas Chromatography Detector for TRACE 1600 Series GC</h3><ul><li>Brochure</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/br_003592_gc_vuv_detector_vga_100_isomers_br003592_na_en_0a48830aff.pdf">Full PDF for download</a></li></ul><h4>Performance synergy—the VGA-100 detector and the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/483">TRACE 1600 Series GC</a>&nbsp;</h4>VUV absorbance and gas chromatography offer a perfect match, joining insights on light absorption in the VUV range with each compound’s unique gas phase absorption features. The innovative VUV absorption technology of the VGA-100, combined with the robust and reliable performance of the Thermo Scientific™ TRACE™ 1600 Series gas chromatograph, offers a powerful analytical solution to support timecritical laboratory demands.&nbsp;Harnessing breakthrough gas chromatography technology, VGA-100 provides unmatched precision and data quality with faster results and higher sample volume. Experience analytical insights with a system designed for ease of use that delivers accurate, reportable results across a diverse range of industries.<h4>Explore the benefits of VUV technology&nbsp;</h4>The unique capabilities of the VGA-100 detector for the TRACE 1600 Series GC help solve common challenges, such as correct isomer identification, poor selectivity, long method run times, analyte co-elution, burdensome data processing and analysis, and method scalability to production environments.&nbsp;<h5>Expand detectable compounds.&nbsp;</h5>Access to a wider range of analytes with enhanced sensitivity towards impurities as well as accurate sample profiling, thanks to the combined universal and selective response of the VGA-100 detector.&nbsp;<h5>Unambiguous identification.&nbsp;</h5>The VGA-100 universal mass-sensitive detector delivers comprehensive data for robust analysis. Data provided in 3D (time, wavelengths, and intensity) supports reliable identification through spectra that can be matched to a dedicated library, including isomers discrimination.&nbsp;<h5>Ease of use and maintenance.&nbsp;</h5>Robust and easy to set up and operate, the VGA‑100 requires minimal maintenance, with no vacuum pumps required. An intuitive design supports high demands for throughput and compliance, supporting the needs of both research and quality control laboratories.&nbsp;<h5>Faster analysis.&nbsp;</h5>Obtain rapid and accurate results with the advanced capabilities of VUV technology, complemented by the fast and efficient chromatographic separation of the TRACE 1600 Series GC.&nbsp;<h5>VUV Analyze Software for push-button simplicity&nbsp;</h5>The advanced post-acquisition processing capabilities of VUV Analyze™ Software (VUV Analytics, Inc.) allows laboratories to generate meaningful results with just the push of a button. This cutting-edge software platform swiftly analyzes complex chromatographic and spectral data, delivering method-specific results and reports. By automating the analysis process, VUV Analyze Software significantly streamlines and speeds up each run while minimizing errors, leading to greater confidence in results.

News from LabRulezGCMS Library - Week 41, 2025

<h4>Abstract&nbsp;</h4>Environmental laboratories are always searching for techniques to increase productivity. However, environmental methods demand a large amount of background information in order to ensure sampling and analysis is compliant. The determination of <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=45&amp;search=VOC">Volatile Organic Compounds (VOCs) </a>in the United States Environmental Protection Agency (USEPA) <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=45&amp;search=Method+8260">Method 8260</a> encompasses many different matrices and in doing so has numerous sampling, quality control, and calibration requirements. The matrices of Method 8260 samples can also vary from air to sludge and from clean to extremely contaminated. Furthermore, the method has an extensive calibration range. All of these factors play into the complexity of sampling and analysis thus, creating ways to streamline sampling while still maintaining sample integrity and method compliance is always of interest to environmental laboratories.<h4>Introduction</h4>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.&nbsp;<h4>Discussion</h4>There are a number or techniques that can enable an analyst to save time in an environmental lab. Analysts can decrease analytical trap bake times, change sample purge time and flow, utilize a dual sampling system for one GC/MS, etc. However, one of the most basic ways to save time is by reducing the number of required curves and standards needed.EST Analytical has designed a patented, automated water sampling mode that will allow environmental laboratories to run water samples in the soil mode. Thus, water and soil curves, standards, blanks and samples can use the same sampling parameters. (See steps 1, 2, and 3 below). This innovative sampling mode would eliminate the need to have separate curves, standards, etc. for soils and waters, thus saving laboratories time and money. Please note that this procedure may only be used with auditor approval.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Experimental_9f34a58017.jpg" alt="EST Analytical: Sampling" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Experimental_9f34a58017.jpg 245w," sizes="100vw" width="1386" height="861"><h4>Experimental</h4>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">EST Analytical Centurion WS autosampler</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">Evolution concentrator</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?mainauthorItems=10&amp;search=7890A">Agilent 7890A GC</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=5975C">5975 inert XL MS</a>. The GC was configured with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=7&amp;search=Restek+Rxi-624+Sil+MS">Restek Rxi-624 Sil MS</a> 30m x 0.25mm x 1.4µm column. The experiments were run using the extraction mode of the Centurion WS. Sampling method parameters and GC/MS parameters are listed below.<h5>Purge and Trap Parameters</h5><ul><li>Concentrator: EST Evolution</li><li>Trap type: Vocarb 3000</li><li>Valve oven temperature: 150 °C</li><li>Transfer line temperature: 150 °C</li><li>Trap temperature: 35 °C</li><li>Moisture Reduction Trap (MoRT) temperature: 39 °C</li><li>Purge time: 11 min</li><li>Purge flow: 40 mL/min</li><li>Dry purge Temp.: Ambient</li><li>Dry Purge Flow: 40mL/min</li><li>Dry Purge Time: 1.0 min &nbsp;</li><li>Desorb pressure Control: ON</li><li>Desorb Pressure: 5psi</li><li>Desorb time: 0.5 min</li><li>Desorb preheat delay: 5 sec</li><li>Desorb temperature: 260 °C</li><li>MoRT bake temperature: 230 °C</li><li>Bake temperature: 270 °C</li><li>Sparge vessel bake temperature: 120 °C</li><li>Bake time: 8 min</li><li>Bake flow: 40 mL/min</li></ul><h5>Auto-Sampler (EST Centurion WS):</h5><ul><li>Sample type: Water Extraction</li><li>Sample Fill Mode: Syringe</li><li>Sample Volume: 10mL</li><li>IS Volume: 5µl</li><li>Needle Rinse Time: 20 sec</li><li>Needle Sweep Time: 20 sec</li><li>Concentrator Desorb Time: 0.5 min</li><li>Syringe Rinse: On/12mL</li><li>Number of Syringe Rinses: 2</li><li>Sparge Rinse Time: Off</li><li>Water Heater Temp.: 85°C</li></ul><h5>GC/MS Parameters</h5><ul><li>System: Agilent 7890/5975 inert XL</li><li>Inlet: Split mode, 200 °C, 40:1 split ratio, 12.153 psi head pressure</li><li>Column: Restek Rxi-624Sil MS, 30 m × 0.25 mm × 1.4 µm</li><li>Oven program: 45 °C (1 min) → ramp 15 °C/min → 220 °C, hold 1.3 min</li><li>Column flow rate: 1 mL/min helium</li><li>Total flow: 44 mL/min</li><li>Source temperature: 230 °C</li><li>Quadrupole temperature: 150 °C</li><li>Transfer line temperature: 180 °C</li><li>Scan range: m/z 35–265, 3.12 scans/sec</li><li>Solvent delay: 0.7 min</li></ul>The USEPA Method 8260 standards were acquired from Restek. The linear range of the water extraction experiment was established by running a nine point calibration curve with a range of 0.5 to 200ppb. Method detection limits were also established for each compound by examining seven replicate standards of the low calibration point. Finally, precision and accuracy were determined by running seven replicate midpoint standards. Figure 1 displays a 50ppb Method 8260 standard chromatogram of a water sample run in soil mode and experimental results are listed in Table 1.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Obrazek_1_Chromatogram_50_ppb_vzorku_vody_analyzovaneho_v_rezimu_puda_55ffcb4ba3.jpg" alt="EST Analytical: Figure 1: 50ppb Chromatogram of a Water Sample Run in Soil Mode" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Obrazek_1_Chromatogram_50_ppb_vzorku_vody_analyzovaneho_v_rezimu_puda_55ffcb4ba3.jpg 245w," sizes="100vw" width="1444" height="514"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Tabulka_3_Vysledky_experimentu_cast_1_7cadc58cda.jpg" alt="EST Analytical: Table 3: Experimental Results_part 1" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Tabulka_3_Vysledky_experimentu_cast_1_7cadc58cda.jpg 215w," sizes="100vw" width="1568" height="1143"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/EST_Analytical_Tabulka_3_Vysledky_experimentu_cast_2_f676814e52.jpg" alt="EST Analytical: Table 3: Experimental Results_Part 2" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_EST_Analytical_Tabulka_3_Vysledky_experimentu_cast_2_f676814e52.jpg 245w," sizes="100vw" width="1571" height="616"><h4>Conclusion</h4>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.

A Single Calibration Method for Water AND Soil Samples Performing EPA Method 8260

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!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">LabRulezLCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you poster by Agilent Technologies / AOAC and application notes by EST Analytical, Shimadzu and Thermo Fisher Scientific!<h3>1. Agilent Technologies / AOAC: Analysis of Pesticides in Spices with Hydrogen Carrier Gas</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">Full PDF for download</a></li></ul>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.<h4>Experimental</h4>An Agilent <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890+GC">8890 GC</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">7010 Triple Quadrupole GC/MS</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.<h4>Results and Discussion&nbsp;</h4>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;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.<h4>Conclusions</h4>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.<h3>2. EST Analytical: A Single Calibration Method for Water AND Soil Samples Performing EPA Method 8260</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">Full PDF for download</a></li></ul>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.<h4>Experimental</h4>The sampling system used for this study was the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2159">EST Analytical Centurion WS autosampler</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2160">Evolution concentrator</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">Agilent 7890A GC</a> and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?search=5975">5975 inert XL MS</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">Restek Rxi-624 Sil MS </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.<h4>Conclusion</h4>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.<h3>3. Shimadzu: Measurement of Volatile Organic Compounds in Water by Headspace GC-MS with Nitrogen Carrier Gas</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">Full PDF for download</a></li></ul>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">GCMS-QP2050</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">HS-20 NX headspace sampler</a> in trap mode.<h4>Samples and Analysis Conditions&nbsp;</h4>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.<ul><li>GC-MS: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GCMS-QP2050">GCMS-QP2050</a></li><li>Head Space Sampler: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20+NX">HS-20 NX</a></li></ul><h4>Conclusion&nbsp;</h4>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.<h3>4. Thermo Fisher Scientific: Enhanced trace moisture analysis in organic solvents using GC with multi-channel VUV detection</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">Full PDF for download</a></li></ul>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;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.The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=3&amp;search=LUMA%E2%84%A2+VUV+detector">LUMA™ VUV detector </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;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;<h4>LUMA detector highlights&nbsp;</h4><ul><li>Detection range: 125–1,050 nm VUV-UV-VIS&nbsp;</li><li>Channel configuration: Up to 12 discrete absorbance bands simultaneously acquired&nbsp;</li><li>Sensitivity: Low-ppb to percent level in a single method&nbsp;</li><li>Installation: Compact, uses any carrier gas and no vacuum pumps&nbsp;</li><li>Software integration: Fully controlled via Thermo Scientific™ Chromeleon™ Chromatography Data System (CDS)&nbsp;</li></ul>These capabilities enable detection of water and organic solvents in a single injection—dramatically simplifying workflows in quality control laboratories.<h4>Experimental&nbsp;</h4>The LUMA detector can be easily installed on a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/483">Thermo Scientific™ TRACE™ 1600 Series GC</a> and controlled in <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/76">Chromeleon CDS</a>, providing method settings, data acquisition, and reporting in a single software platform.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.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;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.<h4>Key application benefits&nbsp;</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>This workflow is aligned with recent trends toward hybrid analytical techniques that reduce resource consumption and speed up decision-making in GMP labs.&nbsp;<h4>Conclusion</h4>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;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;<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>

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