Pesticides and biocides are widely used in agriculture, building materials, and urban gardening to control pests and protect crops and public health. While much attention has been paid to pesticide residues in food, water, and outdoor environments, far less is known about their presence inside homes, where people spend the majority of their time. A new RECETOX study published in Indoor Environments addresses this gap by examining pesticides detected in house dust and their relevance for human exposure.&nbsp;The study reveals that Czech household dust commonly contains multiple pesticide residues, highlighting the persistence of both historic and current chemical use indoors. Modern pesticides were detected in 93% of homes, with two fungicides (carbendazim and propiconazole) most frequently found, while compounds related to the long‑banned pesticide DDT were present in dust from all homes, and were at higher levels in homes over 40 years old. Homes located closer to agricultural areas showed higher levels of current‑use pesticides in spring, indicating an influence of nearby farming activities. &nbsp;House dust acts as a sink for chemicals transported indoors from outdoor sources as well as from indoor use. Many pesticides can persist in dust for long periods, leading to continuous exposure in indoor spaces. This is particularly important for young children, who have higher exposure to dust from playing on the floor and mouthing toys and objects. The research underscores that indoor environments are not isolated from their surroundings. Understanding what ends up in house dust is a crucial step toward protecting public health and developing more comprehensive approaches to managing chemical risks in everyday life.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/RECETOX_Vyzkum_pesticidu_v_domacim_prachu_opomijena_cesta_lidske_expozice_a9a089fd2f.jpg" alt="RECETOX: Pesticides in House Dust: An Overlooked Pathway of Human Exposure" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_RECETOX_Vyzkum_pesticidu_v_domacim_prachu_opomijena_cesta_lidske_expozice_a9a089fd2f.jpg 195w," sizes="100vw" width="738" height="591"><blockquote><h4>Original Article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.sciencedirect.com/science/article/pii/S2950362026000214?via%3Dihub">Legacy and current-use pesticides in indoor settled dust and association with building age and seasonality</a></h4>Paula Marcinekova, Ondřej Mikeš, Simona Rozárka Jílková, Petr Šenk, Jakub Martiník, Jan Böhm, Petra Borilova Linhartova, Lenka Andrýsková, Jana Klánová, Lisa MelymukIndoor Environ., 2026, 3, 100169<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1016/j.indenv.2026.100169">https://doi.org/10.1016/j.indenv.2026.100169</a>&nbsp;<h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote><h4>Abstract</h4>Indoor pesticide exposure is increasingly recognized as a significant contributor to pollutant exposure in residential spaces. This study investigates concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in settled dust from 116 homes in the Czech Republic, in the context of their seasonal variability, relationships with building characteristics, geospatial factors, and indoor dust bacteriome diversity and composition. CUPs were detected in dust in 93% of homes, with carbendazim (84.5%), propiconazole (49.1%), atrazine (24.1%), and tebuconazole (11.2%) detected most frequently. OCPs were found in all homes. Propiconazole concentrations were significantly higher in homes with adjacent gardens, potentially reflecting its use as a biocide in outdoor building materials. CUP concentrations had clear seasonal trends, with peak levels in spring and summer, corresponding to pesticide application periods, particularly in rural environments. OCP concentrations were substantially higher in houses over 40 years old, indicating the persistence of residues from past indoor uses. While pesticide presence was ubiquitous, exposure estimates for children, under both average and high-exposure scenarios, were well below U.S. EPA reference doses (RfDs) for individual compounds; however, most homes had 3–11 pesticides in dust, raising the possibility of mixture effects. No significant associations, using a Spearman rank correlation matrix, were observed between pesticide concentrations and indoor dust bacteriome diversity and composition. These findings highlight the presence of pesticides in homes, including those in urban areas, driven by both current and historical sources, and reinforce the importance of monitoring to better understand potential exposure pathways.<h4>Instrumentation</h4><h5>1. LC–MS/MS analysis of CUPs</h5><ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?instrumentationItems=27&amp;mainauthorItems=10&amp;search=1290+Series+Gradient">Agilent 1290 Series Gradient HPLC</a></li><li>Columns:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1701">Phenomenex Luna C18</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?instrumentationItems=34&amp;mainauthorItems=50&amp;search=SecurityGuard+C18">Phenomenex SecurityGuard C18</a></li></ul></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=55&amp;search=QTrap+5500%2B">SCIEX QTrap 5500+</a> (triple quadrupole MS, ESI+)</li></ul><h5>2. GC–MS/MS analysis of OCPs</h5><ul><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=1&amp;mainauthorItems=10&amp;search=8890A">Agilent 8890A GC</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=19&amp;mainauthorItems=7&amp;search=Rxi-5Sil-MS">Restek Rxi-5Sil-MS capillary column</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7000D">Agilent 7000D triple quadrupole MS</a></li></ul>

Pesticides in House Dust: An Overlooked Pathway of Human Exposure

🎤 Presenter: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/articles?search=petr+vozka">Petr Vozka</a> (California State University LA)💾 <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/paper/32783">PDF presentation</a><h3>Abstract</h3>Microplastics (MPs) are pervasive pollutants throughout our local marine environments. They serve as vectors for organic compounds, yet the variability of their adsorbed contaminants along highly urbanized coastlines remains poorly resolved.This study examines the variation in MP contamination and its associated organic compounds across three beach sites in the greater Los Angeles region. Surface sediments will be collected from each site. MPs will be isolated through a density separation to remove inorganic components, followed by oxidative digestion of the remaining organic matter. The recovered MPs will be characterized using an inlet capable of high-temperature thermal desorption/pyrolysis coupled with two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOFMS) to identify polymer-specific marker compounds and thereby determine MP composition and relative abundance at each location. In addition, a preliminary thermal desorption (TD) step will be applied before pyrolysis to assess organic compounds adsorbed to MP surfaces. Chromatographic profiles from the single-step <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?instrumentationItems=13-3-2-11-8">TD/PY-GC×GC-TOF-MS</a> analyses will be statistically compared among sites using <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/1873">Chromatof Sync 2D software</a> to evaluate differences in both polymer types and co-occurring contaminants. The results will provide insight into how local sources, hydrodynamics, and land use patterns influence the distribution of MP polymers and their adsorbed contaminant loads along urbanized Southern California coastlines.<h3>Video Transcription</h3>In this presentation, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/articles?search=petr+vozka">Petr Vozka</a> (California State University, Los Angeles) addresses a critical analytical challenge associated with chemical recycling of plastics—namely, the detailed characterization of unsaturated hydrocarbons (olefins) formed during depolymerization processes.Plastic waste recycling remains a major global issue, with most materials still ending up in landfills. Emerging thermochemical and catalytic recycling approaches convert plastic waste into fuel-like products. However, these products are highly complex mixtures containing a broad distribution of hydrocarbons, particularly olefins, whose accurate quantification and classification remain analytically demanding.Unlike conventional petroleum-derived fuels, plastic pyrolysis oils may contain up to ~50 wt.% olefins, making traditional analytical methods insufficient.<h4>Why Olefin Characterization Matters</h4>Olefin content directly impacts:<ul><li>Fuel stability and reactivity</li><li>Downstream upgrading processes</li><li>Material compatibility and storage</li><li>Environmental and regulatory compliance</li></ul>However, most standard methods (e.g., bromine number, FIA) only provide bulk unsaturation metrics and lack structural resolution.Additionally, these methods can produce misleading results, especially in complex matrices:<ul><li>Misclassification of compounds (e.g., dienes or heteroatom species as aromatics)</li><li>Poor performance at high olefin concentrations</li><li>Limited chemical specificity</li></ul><h4>Role of GC×GC-FID in Complex Hydrocarbon Analysis</h4>To address these challenges, the group employs comprehensive two-dimensional gas chromatography (GC×GC) with FID detection, which offers:<ul><li>High peak capacity</li><li>Structured chromatographic separation</li><li>Quantitative robustness for hydrocarbons</li></ul>Using reverse-phase GC×GC, hydrocarbons can be organized into regions:<ul><li>n-alkanes</li><li>isoalkanes</li><li>cycloalkanes</li><li>aromatics</li></ul>However, a key finding of this work is that olefins are not confined to a single chromatographic region, as often assumed in literature. Instead:<ul><li>Mono-unsaturated compounds co-elute with isoalkanes and monocycloalkanes</li><li>Di- and poly-unsaturated species appear in higher-order cyclic regions</li><li>Distribution follows a systematic trend linked to double bond count</li></ul>This significantly complicates direct quantification.<h4>Approach 1: GC×GC Combined with Selective Adsorption</h4>The first strategy combines GC×GC-FID with silver-modified silica adsorption:Principle:<ul><li>Olefins are selectively retained on the cartridge</li><li>Sample is analyzed before and after treatment</li><li>Olefin content is calculated from peak area differences</li></ul>Key features:<ul><li>Sample volume: ~50 µL</li><li>Analysis time: ~15 minutes</li><li>Quantification based on weight % (FID response)</li></ul>Advantages:<ul><li>Simple and cost-effective</li><li>Provides group-type quantification</li><li>Suitable for high-olefin samples</li></ul>Limitations:<ul><li>Reliable only above ~5 wt.% olefins</li><li>Primarily applicable to aliphatic olefins</li><li>Limited performance for heavier or aromatic systems</li><li>Co-elution effects may distort alkane quantification</li></ul>Notably, results showed that alkanes can be overestimated if olefins are not properly removed prior to quantification.<h4>Approach 2: Chemical Derivatization for Olefin Identification</h4>The second strategy focuses on chemical derivatization of double bonds, enabling more detailed structural analysis.<h5>Classical Method: DMDS Derivatization</h5><ul><li>Reagent: dimethyl disulfide (DMDS) + iodine</li><li>Reaction at ~70 °C for 1 hour</li><li>Converts olefins into heavier, more polar derivatives</li><li>Shifts peaks to different regions in GC×GC space</li></ul>Outcome:<ul><li>Enables differentiation between saturated and unsaturated species</li><li>Allows carbon-number-resolved quantification</li><li>Provides detailed group-type analysis</li></ul><h5>Limitations:</h5><ul><li>DMDS not sufficiently heavy → incomplete chromatographic shift in complex samples</li><li>Overlap with aromatic region complicates interpretation</li><li>Formation of DMDS-related artifacts</li><li>Requires elevated temperature</li><li>Regulatory challenges (iodine handling)</li></ul><h4>Next-Generation Derivatization Strategy</h4>To overcome these limitations, the group explored alternative disulfide reagents with improved properties:<ul><li>Higher molecular weight → better chromatographic separation</li><li>Improved polarity → enhanced peak shifting</li><li>Reaction at room temperature</li><li>Reduced reliance on iodine (under development)</li></ul>Verification using ¹H NMR confirmed complete consumption of double bonds, demonstrating full derivatization.This new approach significantly improves applicability for:<ul><li>Jet fuel and diesel-range samples</li><li>Highly complex pyrolysis oils</li><li>Advanced structural characterization</li></ul><h4>Analytical Impact and Future Directions</h4>This work demonstrates that combining GC×GC with targeted sample preparation strategies enables:<ul><li>Detailed olefin quantification beyond bulk parameters</li><li>Improved classification of complex hydrocarbon mixtures</li><li>Better understanding of plastic depolymerization pathways</li></ul>Future developments include:<ul><li>Integration with TOF-MS for structural confirmation</li><li>Potential coupling with VUV detection</li><li>Full method validation across feedstocks</li><li>Expansion toward aromatic olefin analysis</li></ul><h4>Conclusion</h4>Accurate characterization of olefins in plastic recycling streams requires moving beyond conventional bulk methods. The combination of GC×GC separation with selective adsorption and advanced derivatization provides a powerful analytical toolbox for resolving these complex systems.This work highlights the importance of method development tailored to emerging matrices, particularly in the context of circular economy and sustainable materials.<blockquote>This text has been automatically transcribed from a video presentation using AI technology. It may contain inaccuracies and is not guaranteed to be 100% correct.</blockquote>

Counting Double Bonds: GCxGC–FID For Plastic Pyrolysis Oils (Petr Vozka, MDCW 2026)

Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 27th April 2026? 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 note by Shimadzu, scientific article by BaySpec, poster by MDCW / JEOL and technical note by Thermo Fisher Scientific!<h3>1. BaySpec: PNNL and BaySpec Launch Compact Mass Spectrometry System for Rapid Narcotics Detection</h3><ul><li>Scientific article</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/PNNL_and_Bay_Spec_Launch_Compact_Mass_Spectrometry_System_for_Rapid_Narcotics_Detection_087ddb9b7e.pdf">Full PDF for download</a></li></ul>The U.S. Department of Energy’s Pacific Northwest National Laboratory’s (PNNL) VaporID, which is a newly developed portable air sampling system incorporating a miniaturized mass spectrometer (MS), can detect trace levels of fentanyl, methamphetamine, cocaine, and even explosives like TNT with great accuracy, the laboratory announced in a press release (1). Because of its success, BaySpec, an optical products manufacturer, is commercializing this instrument, which will be produced later in 2025 (1,2).&nbsp;The new system employs a technique known as noncontact detection, which collects airborne molecules and analyzes them in real time using a miniature mass spectrometer (1). The VaporID device was first developed in 2020. The device won GeekWire’s Innovation of the Year award that same year (2). At the 2025 American Society for Mass Spectrometry (ASMS) conference in Baltimore Maryland, Krisztian Torma, a BaySpec scientist and one of the lead developers, presented the latest test results of the device. The VaporID device was field-tested at the U.S.–Mexico border crossing in Nogales, Arizona. Working with the U.S. Customs and Border Protection (CBP) agency, the device was able to successfully identify trace amounts of fentanyl, as well as other narcotics including MDMA (ecstasy), methamphetamine, ketamine, and cocaine (1).Fentanyl, explosives, and other drugs have low vapor pressure, which means that they do not willingly evaporate and release very few molecules into the air. Given the fact that there are often other interfering chemicals in the air, this presents a detection challenge. The VaporID system overcomes this hurdle by filtering out irrelevant vapors and enhancing signal clarity (1).&nbsp;The success of the VaporID system is the result of a two-year collaboration between PNNL and BaySpec. With plans to commercialize the system by the end of the year, BaySpec aims to bring this advanced narcotics and explosives detection tool into routine use at ports of entry, airports, shipping facilities, and public event venues (1).<h3>2. MDCW / JEOL: ANALYSIS OF AROMA COMPOUNDS IN SPICES BY COMPREHENSIVE TWO-DIMENSIONAL GAS CHROMATOGRAPHY/TIME-OF-FLIGHT MASS SPECTROMETRY WITH MACHINE LEARNING-BASED STRUCTURE ELUCIDATION AND MOLECULAR FORMULA ESTIMATION</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/P_9_Kubota_90c993d536.pdf">Full PDF for download</a></li></ul><section><div><div><div><div><div><div>In GCxGC-MS, compound identification is commonly performed by searching the NIST database (DB) using electron ionization (EI) data. However, some compounds are not registered in the NIST DB. In addition, molecular formula estimation from molecular ions obtained by soft ionization often results in a large number of candidate formulas. To address these issues, we developed two machine learning (ML)–based methods for molecular formula recommendation and structural formula estimation. In this study, these methods are applied to the analysis of aroma compounds in spices using SPME-GCxGC-TOFMS.<h4>Experiments</h4><ul><li>Sample: 0.25 mg dried cardamom seeds&nbsp;</li><li>GC-HRTOFMS: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=23&amp;search=JMS-T2000GC">JMS-T2000GC</a> (JEOL)&nbsp;<ul><li>SPME Fiber: DVB/CAR/PDMS fiber (20 mm, 50/30 μm) at 50°C for 30 min.&nbsp;</li><li>GCxGC Thermal modulator: INSIGHT-Thermal (Sepsolve)&nbsp;</li><li>Modulation period: 6 s&nbsp;</li><li>Column: BPX5 30 m, 0.25 mm. 0.25 µm × Rxi-17Sil MS 3.4 m, 0.15 mm, 0.15µm</li><li>Ionization: Electron ionization (EI) and Field ionization (FI).&nbsp;</li></ul></li><li>Data processing: msFineAnalysis AI (JEOL)</li></ul><h4>Conclusion</h4>We reported two machine learning (ML)-based methods for molecular formula recommendation and structural formula estimation, and applied them to the analysis of aroma compounds. Our method is considered effective for rapid structural estimation of unknown compounds in GCxGC-MS measurements.<h3>3. Shimadzu: HS-GC Analysis of Sake Aroma Compounds Using Hydrogen 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_00886_en_974e971712.pdf">Full PDF for download</a></li></ul><h5>User Benefits</h5><ul><li>Aroma compounds in alcoholic beverages can be quantified easily and cost-effectively.</li><li>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> enables simple, high-sensitivity analysis of aroma compounds.</li><li>Using hydrogen as the carrier gas reduces costs while maintaining separation performance.</li></ul>Aroma is a crucial component of sake. Therefore, during the sake production process, it is essential to preserve the sake’s aroma profile. One key step in sake production is pasteurization (“hiire”), in which unpasteurized sake is heated to sterilize it, deactivate enzymes, and halt fermentation. This pasteurization step is known to impair the aroma of sake if it is carried out for too long or at too high a temperature. In this analysis, a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis+GC-2030">Nexis GC-2030 gas chromatograph</a> was combined with an HS-20 NX headspace sampler (Fig. 1) to quantify individual aroma compounds in sake before and after pasteurization.&nbsp;Headspace gas chromatography (HS-GC) is an effective method for analyzing volatile compounds, including aromas. HS-GC requires no pretreatment (e.g., derivatization), and sample preparation is straightforward: simply place the sample in a vial and perform the analysis.&nbsp;Hydrogen, which is inexpensive and readily available, was used as the carrier gas. Using H2 gas as the carrier reduces analysis costs while maintaining high separation performance over a wide range of linear velocities. However, because hydrogen is flammable, it must be handled with care. The <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis+GC-2030">Nexis GC-2030</a>, <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Brevis+GC-2050">Brevis GC-2050</a>, and <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis+GC-2060">Nexis GC-2060</a> gas chromatographs can be equipped with an optional hydrogen sensor that measures H2 concentration in the column oven. If the hydrogen sensor detects a leak, the system shiftsto standby mode or automatically powers off, helping prevent accidents before they occur.<h4>Conclusion</h4>By combining the Nexis GC-2030 gas chromatograph with the HS-20 NX headspace sampler, the aroma compounds can be easily quantified without pretreatment such as derivatization. In addition, using inexpensive, readily available H2 as the carrier gas reduces analysis costs while maintaining high separation performance. Because the Nexis GC-2030 can be equipped with an optional hydrogen sensor, analyses using H2 carrier gas can be performed safely.<h3>4. Thermo Fisher Scientific: “Outside the box” Raman spectroscopy: Remote measurements for bulk samples</h3><ul><li>Technical note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/remote_measurements_for_bulk_samples_tn1524_en_498225b670.pdf">Full PDF for download</a></li></ul>The effectiveness of Raman spectroscopy depends, in general, on focusing the excitation laser onto the sample. However, there are many cases where a traditional spectrometer’s working distance is not sufficient to achieve this, in which case a focus-independent, long-distance collection proves invaluable. One potential application of this focus-independent “remote” measurement is high-throughput plastics recycling, where many differently sized plastics are passed along at a fixed distance and screened for specific material identification. Similarly, any potential use cases of samples inside a glove box or within a hazardous environment may benefit from long-distance collection, because the laboratory grade spectrometer can be kept clear of the sample enclosure while providing excellent spectral signal. It should be noted that each unique application comes with its own optical beam path and laser safety requirements.In addition to this particular modality, the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2238">Thermo Scientific™ DXR3 Flex Raman Spectrometer</a> provides excellent experimental versatility with micro scale, bulk sampling, and fiber probe collection modes also available. Shown below is a longdistance analytical setup in which the DXR3 Flex Raman spectrometer passes the unfocused laser beam through a quartz shielding window onto a polystyrene sample (Figure 1). The relationship between pathlength/sample mounting preparation and spectral signal is investigated below, to validate the use of a long-distance collection mode as a viable alternative to more traditional, focus-dependent analysis. It is worth mentioning the practice of standoff Raman spectroscopy, a technique designed to provide Raman data at distances ranging from 1 m to several hundred meters. However, these systems often require significantly different components than a standard Raman spectrometer, such as pulsed lasers, gated detectors, UV excitation wavelengths, and telescopic focusing elements.¹ The work described here performs measurements at a distance with a simple, off-the-shelf, benchtop spectrometer.<h4>Practical use case: recycled plastic identification&nbsp;</h4>One of the major benefits of this long-distance measurement technique is being able to handle samples of various sizes and thicknesses without needing to adjust the laser focus for specific samples. The following results simulate a potential use case where remote Raman spectroscopy is used to rapidly identify the plastic materials of various sizes. The samples were fixed at a 50 cm pathlength, and collection times were set at 10 s.All three samples show clear and identifiable Raman signals. The plastic drum is identified as polyethylene, while the water bottle is a specific, BPA-free polycarbonate alternative. The plastic bag is multilayered, with signals from both polyethylene and polycarbonate, along with a visible fluorescence peak at 2150 cm-1. All of these different polymers are spectroscopically identifiable, and at a range of different sample thicknesses. These results provide an excellent view into the use of this technique on non-reference samples. This is just one example of a potential use for the long-distance collection mode, a mode which enables much greater versatility in experimental design and instrument placement.</div></div></div></div></div></div></section>

News from LabRulezGCMS Library - Week 18, 2026

Article

Application

Video

Health

Presentation

Science and research

Poster

RECETOX (Research Centre for Toxic Compounds in the Environment) is an independent department of the Faculty of Science of Masaryk University in Brno, which has been established in 1983. RECETOX is focused on the research and education in cross-cutting area of Environment and Health. It addresses interactions among chemicals, environment, and biological systems, including consequences at local, regional, and global levels.

RECETOX - Centrum pro výzkum toxických látek v prostředí

The Multidimensional Chromatography (MDC) Workshop draws experts in this exciting field to share and discuss their research.

The Multidimensional Chromatography Workshop

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LECO Multi-Mode Source

Multi-Mode Source (MMS) integrates EI, PCI, and NCI/ECNI in a single GC-MS ion source, enabling instant software-based mode switching with perfect peak alignment and enhanced unknown identification.

The innovative Multi-Mode Source (MMS) integrates the strengths of the three most widely used GC-MS ionization techniques—Electron Ionization (EI), Positive Chemical Ionization (PCI), and Negative Chemical Ionization (NCI/ECNI)—into a single, easy-to-use source. With MMS, switching ionization modes is software-controlled and instantaneous, eliminating hardware changes and alignment concerns.Paired with the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/38">Pegasus GC-HRT+</a>, MMS delivers excellent mass accuracy and high resolution for pseudo-molecular ions, complementing traditional high-resolution EI (HR-EI) to enable comprehensive characterization of unknown compounds. Because the hardware remains untouched during mode changes, chromatographic peaks stay perfectly aligned across ionization modes—simplifying comparison and interpretation.All three ionization modes (EI, PCI, NCI/ECNI) are available for both GC-MS and GC×GC-MS workflows on the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/39">Pegasus GC-HRT+ 4D</a> as well as the Pegasus GC-HRT+ systems.<h3>Key Benefits</h3><ul><li>Three ionization modes in one source: EI, PCI, and NCI/ECNI</li><li>No hardware swapping or realignment: mode changes at the click of a button</li><li>Consistent peak alignment across ionization modes</li><li>Enhanced unknown identification via complementary EI and CI information</li><li>Compatible with GC-MS and GC×GC-MS on Pegasus GC-HRT+ platforms</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Multi_Mode_Source_2_79908249a5/LECO-Multi-Mode-Source-2.jpg" alt="LECO: Multi-Mode Source for the Pegasus GC-HRT+ and Pegasus GC-HRT+ 4D" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Multi_Mode_Source_2_79908249a5/thumbnail_LECO-Multi-Mode-Source-2.jpg 245w," sizes="100vw" width="1817" height="1082">

LECO Chemical Ionization Source

Accurate-mass chemical ionization (HR-CI) for the Pegasus GC-HRT+ enables confident molecular ion confirmation, improved EI library matches, and reliable elemental formula generation for unknown compounds.

Confirm your unknowns with accurate mass chemical ionization (HR-CI), a new option for the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/38">Pegasus GC-HRT+</a>. The Pegasus GC-HRT+ is available with both electron ionization (EI) and HR-CI sources, offering you the option of comparison with classical library spectra (EI) and superior preservation of the molecular ion (HR-CI).<h3>Benefits of Positive ion Chemical Ionization</h3><ul><li>Confirmation of molecular ions</li><li>More confidence in EI library matches</li><li>Propose chemical formulae for unknown or novel compounds</li><li>Reduce possible formulae with accurate mass data</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Chemical_Ionization_Source_bb19256163.jpg" alt="LECO Chemical Ionization Source" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Chemical_Ionization_Source_bb19256163.jpg 245w," sizes="100vw" width="1696" height="644">The spectral transformations illustrated above compare and - . The left side is an example from a mouse liver extract,EI HR CI where soft ionization allows for confident confirmation of a marker in glycemic variability for individuals with type 2 diabetes. The right side demonstrates how - is ideal for forensic drug analysis, as drugs are constantly evolving andHR CI often not present in commercially available libraries.<h3>Standard Features</h3><ul><li>Benzophenone 1 pg sensitivity</li><li>Automated reagent gas flow optimization</li><li>Support for standard CI gases: methane, isobutane, and ammonia, PLUS “choose your own”</li><li>Uncompromised MS performance: speed, accuracy and resolution all at the same time, regardless of intensity</li></ul>

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