EU Regulation 396/2005: Pesticide Residue Testing and the Critical Role of QuEChERS Evaporation in Food Safety

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 4th May 2026? Check out new documents from the field of the gas phase, especially GC and GC/MS techniques!</strong></p><blockquote><p><span style="font-size:20px;">👉 </span><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library"><span style="font-size:20px;"><strong>SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT GCMS AND RELATED TECHNIQUES</strong></span></a></p></blockquote><blockquote><p><strong>👉 Need info about different analytical techniques?</strong> Peek into <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library"><strong>LabRulezLCMS</strong></a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library"><strong>LabRulezICPMS</strong></a> libraries.</p></blockquote><p>This week we bring you application note by<strong> Shimadzu, </strong>presentation by <strong>MDCW / JEOL</strong> and technical note by <strong>Thermo Fisher Scientific!</strong></p><h3><strong>1. MDCW / JEOL: Flow-Modulated GCxGC-QMS Analysis Without Splitting Off the GC Flow</strong></h3><ul><li>Presentation</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/O_16_Jensen_11e29d5022.pdf"><strong>Full PDF for download</strong></a></li></ul><section><div><div><div><div><div><div><p>This presentation by Kirk Jensen (JEOL USA) explores the feasibility of performing <strong>flow-modulated comprehensive two-dimensional gas chromatography (GC×GC) coupled with quadrupole mass spectrometry (QMS)</strong> without splitting the GC flow, which is traditionally required to protect MS systems from high carrier gas flows. The core concept builds on GC×GC, where compounds are separated using a primary and secondary column connected via a modulator, significantly increasing separation power compared to one-dimensional GC. The presentation contrasts <strong>thermal modulation</strong> (offering sharper peaks and higher theoretical sensitivity but requiring cryogenic cooling) with <strong>flow modulation</strong>, which avoids cryogens, handles volatile analytes well, and is more flexible, but typically demands higher gas flows that standard MS systems cannot tolerate .</p><p>To address this limitation, the study utilizes the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?manufacturerItems=24&amp;search=JMS-Q1600GC"><strong>JEOL JMS-Q1600GC</strong></a><strong> UltraQuad quadrupole GC-MS system</strong>, which can accept unusually high carrier gas flows (up to ~20 mL/min), enabling direct coupling with a <strong>SepSolve INSIGHT flow modulator</strong> without splitting the effluent . The analytical setup includes dual GC columns (e.g., Zebron ZB-5MSplus for the first dimension and BPX50 for the second), high secondary flow rates (~25 mL/min), and electron ionization (EI) MS detection. Additional system components include optional FID detection, bleed line control, and ChromeSpace software for data processing . This configuration allows full analyte transfer into the MS, eliminating the need for flow splitting and potentially improving detection efficiency.</p><p>Experimental results demonstrate the applicability of this approach to complex mixtures, including a <strong>pesticide mixture containing over 200 compounds</strong> and real-world samples such as perfumes and fuels. The GC×GC-MS system produced detailed two-dimensional chromatograms with high spectral quality, enabling the correct identification of approximately 120 compounds despite relatively moderate spectral match factors . Comparisons at different flow rates (e.g., 25 vs. 50 mL/min) showed that spectral integrity and compound identification remain robust, indicating that higher flow operation does not significantly compromise MS performance.</p><p>In conclusion, the work demonstrates that <strong>flow-modulated GC×GC-QMS without flow splitting is feasible</strong>, provided that the MS system can tolerate high carrier gas flows. While further optimization is needed (e.g., column selection, inlet pressure, and separation conditions), the approach offers a practical alternative to thermal modulation by eliminating cryogens and simplifying operation. Future work will focus on improving sensitivity, optimizing separations, and exploring alternative carrier gases such as hydrogen to reduce costs and expand applicability</p></div></div></div></div></div></div></section><h3><strong>2. Shimadzu: Detailed Hydrocarbon Analysis by Nexis GC-2030 Using ASTM D6730</strong></h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/an_01_00863_en_eb633bc741.pdf"><strong>Full PDF for download</strong></a></li></ul><h5><strong>User Benefits</strong></h5><ul><li>Detailed compositional analysis of gasoline in accordance with ASTM D6730 is feasible using the Nexis GC-2030.&nbsp;</li><li>By employing PONAsolution, a PONA/DHA analysis software, laborious identification tasks can be reduced, and quantitation calculations and report generation can be performed automatically.</li></ul><p>ASTM D6730 specifies the analysis of hydrocarbons in gasoline and oxygenates such as ethanol, methyl tert-butyl ether (MTBE), and ethyl tert-butyl ether (ETBE) over a boiling point range up to 225 ̊C. Identification and quantification of individual compounds in gasoline are critically important for refinery process control and product quality assurance. In this application news, we report compositional analysis of gasoline conforming to ASTM D6730 using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexis+GC-2030"><strong>Nexis GC-2030 gas chromatograph</strong></a>. Gasoline typically comprises over 100 hydrocarbons, making identification tasks highly complex; however, PONAsolution, a PONA/DHA analysissoftware,simplifies this process.</p><h4><strong>PONAsolution</strong></h4><p>PONAsolution Ver.6 provides retention index libraries for each relevant standard (ASTM D6730, D6729, D5134, D6733). Identification of n-alkanes automatically corrects the retention times of the remaining several hundred components, thus streamlining the identification process. When only a specific retention region requires adjustment, the two-point identification function is useful (Fig. 1). In the two-point identification procedure, reference and sample chromatograms are compared while assigning corresponding peaks. First, click on an identified component mark in the reference data (Fig. 1, a), then click the matching sample peak (Fig. 1, b). Repeat this for a second pair of peaks. The retention times of components between these two anchor points are then automatically corrected.</p><h4><strong>Conclusion</strong></h4><p>Compositional analysis of gasoline in accordance with ASTM D6730 was performed. The combination of SH PONA Tuning Column and SH-1 PONA main column enabled separation of compounds with closely spaced retention times. Moreover, use of PONAsolution software greatly simplifies complex identification tasks.</p><h3><strong>3. Thermo Fisher Scientific: Fiber optic probes add flexibility to Raman chemical analysis</strong></h3><ul><li>Technical note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/drx3_flex_tech_note_tn54708_bebb56b870.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy are non-destructive analytical techniques that rely on the interaction of electromagnetic radiation with molecular vibrations to provide information about the chemical composition and structure of a sample. Despite their similarities, there are some distinct differences between the two techniques. In principle, FTIR is based on the absorption of infrared radiation by molecules and measures changes in dipole moment during molecular vibrations. Raman spectroscopy, on the other hand, is based on the inelastic scattering of monochromatic light and measures changes in polarizability during molecular vibrations.&nbsp;</p><p>When applied to bulk chemical analysis, both FTIR and Raman spectroscopy can be used to analyze solids, liquids, and gases, but the nature of Raman spectroscopy lends some unique sampling advantages. Additionally, Raman often requires little to no sample preparation. Presented herein are application examples that highlight some of the sampling advantages of Raman spectroscopy. All the spectral data in this technical note were collected using a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2238"><strong>Thermo Scientific™ DXR3 Flex Raman Spectrometer</strong></a> equipped with a fiber optic probe. (Fiber optics are readily available for Raman spectroscopy because of the use of visible and NIR light and do not require the exotic materials associated with FTIR fiber optics.) Preliminary tests for all samples were carried out using both 532 nm and 785 nm excitations, and it was determined that the 785 nm laser set gave an overall better balance between fluorescence and Raman scattering efficiency.</p><h4><strong>Summary&nbsp;</strong></h4><p>In this technical note, the analyses of a variety of samples by Raman spectroscopy are demonstrated. All samples were analyzed without sample preparation.&nbsp;</p><ul><li>Precise and localized analysis at the focal point of the Raman-exciting laser allows sampling through glass bottles, blister packaging and plastic containers, which eliminates possible cross contamination and analyst exposure to hazardous materials. The contributions from the packaging and containers depend on the type of container material, the container thickness, and the materials’ chemical compositional complexity, but these contributions can be readily subtracted out when needed.&nbsp;</li><li>Water is a weak Raman scatterer. Raman therefore has reduced water sensitivity, making it a preferred technique for aqueous solution analysis over FTIR. As demonstrated in the analysis of an energy drink, the Raman bands from water can be subtracted from the spectrum of the aqueous solution, leading to the identification of the components of the solution.&nbsp;</li><li>Raman spectroscopy is well suited for the analysis of inorganic materials, especially in identifying the crystal phases and polymorphs, as demonstrated by the analyses of minerals and pigments in a painting.&nbsp;</li><li>Fiber optic probes provide flexibility and ease of maneuverability. This is particularly advantageous when analyzing samples that are difficult to access or manipulate, such as large containers, geological samples and paintings</li></ul><p>The DXR3 Flex has multiple sampling options available. A properly configured fiber-optic probe is arguably the most versatile accessory for the analysis of bulk solids and liquids. The advantages, both from those inherent to Raman spectroscopy and those resulting from the use of fiber optic probe, provide opportunities for a wide variety of different applications when using the DXR3 Flex Raman Spectrometer.</p>

News from LabRulezGCMS Library - Week 19, 2026

<p><strong>🎤Francis Femi Oloy</strong></p><p><strong>In this episode of Concentrating on Chromatography, David speaks with Francis Femi Oloy about using chromatography to uncover hidden pollutants in real-world water systems.</strong></p><p>Femi’s team analyzed polychlorinated biphenyls (PCBs) in six major rivers in southwestern Nigeria — compounds that were banned decades ago but still persist in the environment. Using a workflow that many analytical labs will recognize — liquid–liquid extraction, cleanup, rotary evaporation, nitrogen blowdown, and GC-ECD detection — they quantified 25 PCB congeners at trace levels and linked the results to ecological and human health risk.</p><h4><strong>In this conversation, we cover:</strong></h4><ul><li>Why legacy pollutants like PCBs still show up today</li><li>Choosing GC-ECD vs LC-MS for halogenated compounds</li><li>Liquid–liquid extraction and matrix cleanup strategies</li><li>Why sample concentration is critical for dilute environmental samples</li><li>How rotovap + nitrogen blowdown work together without losing volatile analytes</li><li>Seasonal trends (why wet season levels were higher)</li><li>Translating concentration data into meaningful risk assessments</li></ul><h3><strong>Video Transcription</strong></h3><section><div><div><div><div><div><div><p><strong>Persistent organic pollutants</strong> such as polychlorinated biphenyls (<strong>PCBs</strong>) remain a significant environmental concern despite decades of regulatory restrictions. In this interview, Francais Femi Oloy discusses the environmental and analytical challenges associated with monitoring PCB contamination in rivers of southwestern Nigeria, a rapidly industrializing region where urban growth, industrial activity, agriculture, and dense populations intersect with extensive aquatic systems.</p><p>Oloy explains that his interest in environmental contaminant analysis emerged from observing unexplained health problems and environmental degradation while growing up in Nigeria. This motivated his transition into organic and environmental chemistry, with a focus on identifying pollutants present in drinking water, agricultural soils, and food systems. Southwestern Nigeria, particularly the Lagos region, represents a critical environmental monitoring area due to intense industrial development, shipping activity, and widespread human dependence on rivers for domestic use, agriculture, and fishing.</p><p>Although PCBs are considered “<strong>legacy pollutants</strong>” and are no longer intentionally produced, the interview highlights why they continue to persist in aquatic environments. Old electrical transformers and aging industrial equipment still contain PCB residues, while historical contamination stored in river sediments can become remobilized during flooding, dredging, or sediment disturbance. Because PCBs are hydrophobic and resistant to degradation, they preferentially accumulate in sediments and bioaccumulate through aquatic food chains, creating long-term environmental and human exposure risks.</p><p>A major focus of the discussion centers on the analytical workflow used for PCB determination in environmental water samples. Composite river water samples were collected in amber glass bottles to avoid contamination and photodegradation, preserved with sodium azide to minimize microbial activity, and stored under cooled conditions prior to extraction. The analytical protocol employed <strong>liquid–liquid extraction</strong> using dichloromethane (DCM) and hexane to recover both polar and nonpolar PCB congeners. Oloy emphasizes that liquid–liquid extraction was selected over solid-phase extraction (SPE) because of concerns about congener retention within sorbent materials and clogging issues associated with large-volume environmental samples.</p><p>Following extraction, concentration and cleanup represented critical analytical stages due to the trace-level occurrence and volatility of PCBs. Silica and alumina cleanup procedures were used to remove matrix interferences prior to instrumental analysis. The concentration workflow combined rotary evaporation for bulk solvent reduction with nitrogen blowdown for final volume reduction to less than 1 mL, while carefully avoiding excessive temperature or complete dryness to minimize analyte loss. Oloy repeatedly stresses that improper concentration procedures are among the most common causes of analytical failure in PCB analysis.</p><p>For instrumental determination, the study utilized <strong>gas chromatography coupled with electron capture detection (GC-ECD)</strong> rather than LC-MS or GC-MS. According to Oloy, GC was preferred because PCBs are sufficiently volatile for gas chromatographic separation, while ECD provided superior sensitivity and selectivity for chlorinated compounds at environmentally relevant concentrations. The interview also discusses analytical validation strategies, including the use of surrogate standards to assess <strong>recoveries,</strong> which ranged from approximately <strong>85% to 114%</strong>, and signal-to-noise-based determination of detection limits.</p><p>The study further examined <strong>seasonal variations in PCB concentrations</strong>, revealing <strong>higher levels during the wet season</strong>. This observation was attributed to rainfall-driven runoff from contaminated infrastructure, sediment resuspension, and lower temperatures that reduce volatilization losses. To communicate toxicological relevance beyond simple concentration reporting, the researchers also calculated <strong>toxic equivalency values (TEQs)</strong>, converting mixtures of PCB congeners into biologically meaningful toxicity estimates comparable to dioxin toxicity metrics.</p><p>Beyond environmental monitoring, Oloy highlights broader research interests focused on <strong>pollutant remediation and sustainable environmental protection</strong>. His group is also involved in developing catalytic materials capable of degrading or removing persistent contaminants from environmental systems. Throughout the discussion, he emphasizes that analytical chemistry plays a central role not only in detecting pollutants, but also in enabling prevention, remediation, and long-term environmental management strategies.</p></div></div></div></div></div></div></section><blockquote><p><strong>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.</strong></p></blockquote><blockquote><h4><strong>Concentrating on Chromatography Podcast</strong></h4><p>Dive into the frontiers of chromatography, mass spectrometry, and sample preparation with host David Oliva. Each episode features candid conversations with leading researchers, industry innovators, and passionate scientists who are shaping the future of analytical chemistry. From decoding PFAS detection challenges to exploring the latest in AI-assisted liquid chromatography, this show uncovers practical workflows, sustainability breakthroughs, and the real-world impact of separation science. Whether you’re a chromatographer, lab professional, or researcher you'll discover inspiring content!</p><p>You can find <strong>Concentrating on Chromatography Podcast </strong>in podcast apps:</p><ul><li><a target="_blank" rel="noopener noreferrer" href="https://open.spotify.com/show/1wZg67rCjoGju4yhqxI3tL"><strong>Spotify</strong></a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podcasts.apple.com/tz/podcast/concentrating-on-chromatography/id1788429185"><strong>Apple podcast</strong></a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podscan.fm/podcasts/concentrating-on-chromatography"><strong>podscan</strong></a></li></ul><p>and on <a target="_blank" rel="noopener noreferrer" href="https://www.youtube.com/@ChromatographyTalk/videos"><strong>YouTube channel</strong></a></p></blockquote>

Tracking Toxic PCBs in River Water using Gas Chromatography–Electron Capture Detection

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Organomation, founded in 1959, designs and manufactures high-quality nitrogen evaporators and extraction systems. Known for innovation and durability, their lab instruments are used globally for efficient sample preparation with strong customer support.

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LECO Paradigm Flow Modulator and Shift Flow Splitter

Paradigm RFF Flow Modulator with Shift Flow Splitter boosts GC×GC peak capacity while maintaining constant MS/FID split ratios, enabling accurate, repeatable quantitation across full volatility ranges.

<p><strong>The Paradigm Flow Modulator with Reverse Fill-Flush (RFF) technology dramatically expands chromatographic peak capacity across the full volatility range while preserving quantitative accuracy. The RFF modulator fills a fixed-volume sample loop with effluent from the first-dimension column and then rapidly flushes it onto an orthogonal second-dimension stationary phase. This true comprehensive GC×GC transfer ensures excellent repeatability, robust quantitation, and high-quality separations for complex samples.</strong></p><h3><strong>Key features</strong></h3><ul><li><strong>Reverse Fill-Flush (RFF) modulation</strong> for true comprehensive GC×GC with complete analyte transfer</li><li><strong>Novel chromatography splitter</strong> with two channels of pressure assistance</li><li><strong>Designed for high flows</strong> required for RFF modulation (≈20 mL/min)</li><li><strong>Constant MS/FID split ratio</strong> maintained throughout the entire run, including oven temperature ramps</li></ul><h3><strong>ChromaTOF makes modulation simple</strong></h3><p>Paradigm eliminates complex offline flow calculations. Integrated <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41"><strong>ChromaTOF® software</strong></a> automatically performs all required calculations via a straightforward interface. The resulting methods are optimized to deliver complete analyte transfer, excellent peak shapes, and high chromatographic resolution—without manual trial-and-error.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Chromatof_flow_calculation_6b8ca60f99.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter: ChromaTOF Software identifies method calculation improvements for RFF modulation" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Chromatof_flow_calculation_6b8ca60f99.jpg 245w," sizes="100vw" width="670" height="426"></p><h3><strong>A shift forward in chromatographic analyses</strong></h3><p>The <strong>Shift Flow Splitter</strong> introduces a novel splitting mechanism that maintains a constant split ratio between MS and FID across the full GC oven program. Compared to traditional splitters, Shift delivers superior quantitative accuracy with minimal internal standardization, greatly simplifying compound-level and group-type quantitation in GC and GC×GC workflows.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_LECO_Paradigm_G_Cx_GC_prutokovy_modulator_a_Shift_splitter_5_245c7c2fde.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter:   Close-up on the Shift Flow Splitter installed in a GC oven" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_LECO_Paradigm_G_Cx_GC_prutokovy_modulator_a_Shift_splitter_5_245c7c2fde.jpg 245w," sizes="100vw" width="2925" height="825"></p><h3><strong>Software-optimized detector performance</strong></h3><p>ChromaTOF automatically balances and optimizes the flow directed to TOFMS and FID, ensuring proper peak shapes and matched sensitivity for reliable qualitative and quantitative results.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Optimize_flow_e51d505415.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter:   ChromaTOF Software automatically optimizes flow rates" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Optimize_flow_e51d505415.jpg 207w," sizes="100vw" width="808" height="608"></p>

LECO QuadJet™ SD

GC×GC-FID system combining thermal modulation and ChromaTOF software to reduce coelution bias, boost resolution, and deliver accurate quantitation of complex samples—without sacrificing productivity.

<p><strong>The QuadJet SD is a comprehensive GC×GC-FID solution designed to reveal the true chemical composition of complex real-world samples. By combining the universal sensitivity of flame ionization detection (FID) with the dramatically increased chromatographic resolution of comprehensive two-dimensional gas chromatography (GC×GC), QuadJet SD minimizes coelution-driven bias and delivers a far more accurate representation of sample composition than conventional one-dimensional GC.</strong></p><p>Unlike straight GC-FID, where unresolved peaks inflate detector response and introduce systematic error, GC×GC separates compounds using two orthogonal mechanisms within a single run. True GC×GC instruments—such as the QuadJet SD from <span>LECO</span>—use active modulation to quantitatively slice the effluent from the first column and refocus it onto the second column. This approach preserves quantitative integrity while unlocking orders-of-magnitude gains in peak capacity and signal-to-noise ratio.</p><h3><strong>Key Benefits</strong></h3><ul><li><strong>Enhanced separation power</strong> for highly complex mixtures</li><li><strong>Reduced noise and bias error</strong> compared to conventional GC-FID</li><li><strong>Integrated </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41"><strong>ChromaTOF-based software</strong></a> for acquisition, processing, classification, and reporting in one environment</li><li><strong>Classification tools</strong> that simplify component identification</li><li><strong>Cryogen-free modulation option</strong> eliminates the need for liquid nitrogen dewars</li></ul><h3><strong>Theory of Operation</strong></h3><p>In GC-FID analysis, compound quantitation relies on peak area. As sample complexity increases—diesel fuels being a classic example with thousands of constituents—the likelihood of coelution rises sharply. Coeluting compounds produce artificially elevated FID responses, leading to high-bias errors.</p><p>GC×GC overcomes this limitation by performing two independent chromatographic separations in a single experiment. Thanks to the orthogonal selectivity of the two columns, compounds that coelute in the first dimension are efficiently separated in the second. In the QuadJet SD, eluting peaks from the primary column are quantitatively segmented by the modulator and cryo-focused before entering the secondary column, generating extremely narrow second-dimension peaks—often as short as <strong>50 ms</strong>—while maintaining accurate quantitation.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Quad_Jet_SD_2_bbb51b2254/LECO-QuadJettm-SD-2_l.webp" alt="LECO: QuadJet™ SD 2 – Processing of acquired GC×GC data using LECO ChromaTOF software" width="923" height="543"></p><h3><strong>Thermal Modulation</strong></h3><p>Thermal modulation represents the highest-performance approach for GC×GC, and LECO’s implementation sets the benchmark for ruggedness, reliability, and analytical performance. The QuadJet SD employs a <strong>dual-stage, quad-jet thermal modulator</strong> positioned between the two columns. This design enables on-column cryo-focusing, dramatically improving peak detectability and resolving power, and delivering an <strong>order-of-magnitude improvement in signal-to-noise</strong>.</p><p>For laboratories seeking lower operating costs and simplified workflows, a <strong>consumable-free thermal modulator</strong> (no liquid nitrogen) is available. This option maintains excellent performance for moderately volatile compounds while eliminating cryogen handling.</p><h3><strong>Modulators and Instrument Options</strong></h3><ul><li><strong>Thermal modulator choices</strong>:<ul><li>Liquid-nitrogen-cooled thermal modulator</li><li>Consumable-free thermal modulator</li></ul></li><li><strong>Optional inlets</strong>: S/SL, PTV, and MMI</li></ul><p>Designed with productivity in mind, the QuadJet SD combines ease of use with an industry-leading secondary oven for the second-dimension column. For laboratories ready to move beyond conventional GC and truly see what has been hidden by coelution, QuadJet SD delivers the next dimension in analytical insight.</p>

LECO GCxGC FLUX flow modulator

Flux GC×GC flow modulator simplifies GC×GC analysis using diverting flow principles. It offers robust, cost-effective modulation without cryogens, ideal for complex, concentrated samples.

<p><strong>Our innovative Flux GC×GC flow modulator was designed with one goal in mind—to make GC×GC more routine, accessible, and easier for you. The flow modulator's concept is based on the sound and easily understood principles first articulated by Seeley et al. on diverting flow. This extraordinarily simple design comprising of a cross shape and sideways T, is not only easy to setup and get started, but its ease-of-use makes it the most cost-effective option for GC×GC analysis.</strong></p><p>This flow-based modulator is perfect for those who want to perform robust GC×GC analysis, but who don't need the sensitivity of standard quad jet thermal modulation. Ideal samples should be complex, but relatively concentrated. Appropriate applications include petroleum and fragrance analyses such as the classic weathered crude oil example pictured below, which shows a GC×GC plot generated on our Pegasus® BT platform using the Flux flow modulator.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ee943ea0acb34a8d9c5b72e7ace10666/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="957" height="523"></p><h4><strong>Theory of Operation: Diverting Flow</strong></h4><p>The first and secondary capillary columns are connected together through a simple tube with a fixed gap between the columns. A flow of gas (helium) is then used to inject into the second column or divert to waste. The precision timing and flows are all handled by our integrated software, therefore you just have to click one button to setup and begin performing flow modulation GC×GC on our Pegasus BT platform.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/508b477dd1604d15855f26d786d5b1e4/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="1026" height="488"></p><p>Furthermore, no complex spreadsheets are needed to understand your method. This simple and robust design does not require cryogens to carry out GC×GC, which saves time and boosts efficiency in your lab.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/6796d4581c894291b9fab0088753cb8b/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="918" height="545"></p>

LECO QUADJET Thermal Modulator

Consumable-free dual-stage thermal jet modulator for GC×GC delivering on-column cryo-focusing, higher peak detectability, superior separation, and reliable performance without liquid nitrogen.

<p><strong>The QUADJET Thermal Modulator from </strong><span><strong>LECO</strong></span><strong> delivers industry-leading performance for comprehensive two-dimensional gas chromatography (GC×GC). Compared to alternative thermal or valve-based modulators, QUADJET stands out for its exceptional ruggedness, long-term reliability, and superior modulation efficiency.</strong></p><p>This GC×GC modulation system uses a <strong>dual-stage thermal jet modulator</strong> positioned between the first- and second-dimension columns. The design enables true <strong>on-column cryo-focusing</strong>, significantly enhancing peak sharpness, detectability, and separation power—especially for co-eluting compounds in complex sample matrices.</p><h3><strong>Key benefits</strong></h3><ul><li><strong>Highest modulation performance for GC×GC</strong><br>Enhances peak detectability and improves separation of co-eluting compounds.</li><li><strong>Dual-stage thermal jet design</strong><br>Provides efficient trapping and re-injection between columns.</li><li><strong>On-column cryo-focusing</strong><br>Improves sensitivity and separation of closely eluting analytes.</li><li><strong>Exceptional robustness and reliability</strong><br>Designed for routine, long-term GC×GC operation.</li></ul><h3><strong>Thermal modulation without liquid nitrogen</strong></h3><p>Unlike traditional cryogenic modulators, the <strong>QUADJET thermal modulator is consumable-free</strong>. It delivers the full performance benefits of thermal modulation <strong>without the need for liquid nitrogen</strong>, eliminating cryogen costs, logistical complexity, and downtime—while maintaining consistent, high-quality results.</p><p>The QUADJET Thermal Modulator is an ideal choice for laboratories seeking <strong>maximum GC×GC performance with minimal operational burden</strong>, particularly in demanding applications involving highly complex samples.</p>

Products from category GCxGC modulators focused on GCxGC from LECO - page 1

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Tracking Toxic PCBs in River Water using Gas Chromatography–Electron Capture Detection

EU Regulation 396/2005: Pesticide Residue Testing and the Critical Role of QuEChERS Evaporation in Food Safety

News from LabRulezGCMS Library - Week 19, 2026