Clarity 10.2 expands instrument control capabilities with new control modules and updates the MS extension to help you work more efficiently.<h4><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/999">Clarity</a> 10.2 highlights</h4><ul><li>New and updated control modules</li><li>Improved MS data import and export</li><li>Obsolete hardware support ended</li></ul><h4>Instrument control modules</h4>Clarity 10.2 introduces new instrument control modules from Annuo (AS-3117, FAS-3823) and updated instrument controls form Sykam and Ecom.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Instrument_control_modules_5de26782b0.jpg" alt="DataApex: Instrument control modules" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Instrument_control_modules_5de26782b0.jpg 228w," sizes="100vw" width="380" height="260"><h4>MS data import/export improvements</h4>Clarity improves MS data exchange, especially for *.cdf files. MS instruments now support export and import of multiple spectral data and non-spectral signal data in the same CDF file. Import also better handles uniform sampling information, m/z Step values, scale factors, and file names with non-ASCII characters. Exporting individual chromatogram signals from MS instruments is now available through a separate Export Chromatogram dialog.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_MS_data_import_export_improvements_a7967a4020.jpg" alt="DataApex: MS data import-export improvements" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_MS_data_import_export_improvements_a7967a4020.jpg 228w," sizes="100vw" width="378" height="259"><h4>Obsolete hardware support terminated</h4>Due to changes in Windows driver security requirements, this update discontinues support for obsolete hardware, including INT7, INT9, U-PAD, U-PAD2, and CB20.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Obsolete_hardware_support_terminated_24d9329419.jpg" alt="DataApex: Obsolete hardware support terminated" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Obsolete_hardware_support_terminated_24d9329419.jpg 228w," sizes="100vw" width="378" height="259"><blockquote>Explore the complete list of all changes, fixes, and additions in version 10.2.👉<a target="_blank" rel="noopener noreferrer" href="https://www.dataapex.com/version_history?product=1">See the complete changelog&nbsp;</a></blockquote>

Clarity Chromatography Software 10.2 released!

This study describes the development and validation of a dual-column, dual-detector HS-GC-FID/FID method for the forensic analysis of ethanol and other low-molecular-weight volatile compounds in biological samples. The method demonstrated excellent linearity, low detection limits, high precision, and accuracy, and was successfully verified through international proficiency testing.In addition to routine forensic application, the study reviews current practices in forensic alcohol analysis and highlights the lack of globally harmonized analytical standards. The authors propose essential methodological recommendations to improve the reliability and evidential value of ethanol determination in forensic toxicology.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80">Dual-Column HS-GC-FID/FID Method for In-Depth Analysis of Low-Molecular-Weight Volatile Alcohols in Postmortem Biological Material&nbsp;</a></h4>Paweł Szpot, Olga Wachełko, Kaja Tusiewicz and Marcin ZawadzkiJ. Xenobiot. 2026, 16(3), 80<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.3390/jox16030080">https://doi.org/10.3390/jox16030080</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.<div>The determination of low-molecular-weight volatile alcohols in postmortem material using headspace gas chromatography (HS-GC) is routinely performed in forensic laboratories. These analyses are important not only for law enforcement agencies in the broad sense, but also for insurance companies that decide on the payment of compensation under insurance policies. Typically, routine determination of alcohols such as methanol, ethanol, isopropanol, n-propanol, and n-butanol is sufficient to establish whether death occurred as a result of poisoning with these substances. In forensic toxicology practice, however, there are also situations in which the determination of additional chemical compounds in biological material proves to be essential. One such compound is acetone, the determination of which is crucial not only in cases of acetone or isopropanol poisoning (since acetone is a metabolite of the aforementioned alcohol) [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B1-jox-16-00080">1</a>], but also in the diagnosis of ketosis caused by diabetes, hypothermia, or starvation [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B2-jox-16-00080">2</a>]. Criminal cases can be complex, and therefore, to achieve a better understanding of the circumstances preceding death, toxicological analyses are sometimes extended to also include other compounds, such as acetaldehyde [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B3-jox-16-00080">3</a>].Postmortem blood toxicological analysis is of particular importance because it plays a key role in determining the cause of death, especially in cases of unexplained sudden death and deaths occurring under suspicious circumstances. Even a simple screening for volatile chemical compounds can, at an early stage, allow determination of whether death resulted from poisoning or was a consequence of an underlying disease suffered by the deceased (e.g., untreated diabetes) [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B4-jox-16-00080">4</a>].One of the fundamental assumptions in forensic toxicological investigations is that their results must have evidential value and withstand scrutiny in court. Only such results can be used, for example, to reconstruct the circumstances preceding death, determine the time of substance intake or the dose of a toxic agent, or assess whether the deceased was intoxicated. This is particularly important in cases of traffic accidents, occupational accidents, drownings, domestic violence, and deaths occurring during police custody. It is worth emphasizing that the interpretation of postmortem toxicological results requires particular caution due to the multitude of “confounding” factors, such as interindividual variability, substance stability, endogenous formation, the postmortem interval (PMI), and the circumstances of death. To avoid introducing additional variables that could further complicate interpretation, the applied analytical method must be reliable, i.e., accurate, selective, resistant to interference, and preferably verified through independent proficiency testing [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B5-jox-16-00080">5</a>].In gas chromatographic analysis of low-molecular-weight alcohols, either direct injection or the headspace technique is employed [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B6-jox-16-00080">6</a>]. In the past, even highly invasive approaches were used, such as the direct injection of whole blood into the gas chromatograph injector [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B7-jox-16-00080">7</a>]. However, the headspace technique has become the most widely used technique for the determination of alcohols in forensic laboratories. This preference can be attributed to several well-established advantages, most notably that the method allows the sample to be analyzed with minimal or no preparatory steps, irrespective of the biological matrix (e.g., without extraction or protein precipitation). Additional benefits include practically negligible matrix effects, elimination of the need for inlet liners, thereby minimizing the risk of contamination or carryover within the analytical system, and reduced deterioration of the chromatographic column compared with direct injection.However, it should be noted that in the context of postmortem samples (particularly those collected from putrefied cadavers), the impact of decomposition on analyte partitioning cannot be precisely assessed. While headspace analysis generally exhibits negligible matrix effects, pre-death specimens from the same individual are rarely available for direct comparison, making it difficult to determine the extent to which postmortem changes might influence measurements. Moreover, the blood samples are subjected to multiple dilutions with an internal standard, which further minimizes potential matrix effects.Despite numerous established methods for the determination of volatile alcohols in postmortem biological samples, current standard approaches often face limitations that can compromise forensic reliability. Single-column analyses may be prone to co-elution and interferences from structurally similar compounds, while reliance on a single detector increases the risk of undetected fluctuations and errors. Additionally, inappropriate selection of internal standards and postmortem formation of endogenous alcohols and other volatile compounds can further bias quantification. These issues highlight a critical gap, as widely adopted methods that integrate redundant analytical controls with validated procedures to minimize errors and ensure evidential reliability remain limited.The aim of this study was to develop a method for the determination of methanol, acetone, ethanol, n-propanol, isopropanol, and n-butanol using headspace gas chromatography with dual columns and dual-flame ionization detectors. The practical applicability of the method was demonstrated using authentic forensic samples, including putrefaction fluid and antemortem blood. This study addresses the aforementioned gap by employing a dual-column/dual-FID approach, which allows cross-verification across two independent chromatographic conditions, thereby enhancing both the accuracy and reproducibility of forensic alcohol analysis. Furthermore, this paper aims to draw the attention of toxicologists worldwide to several critical factors that can significantly influence measured ethanol concentrations, potentially leading to legal and financial consequences, such as denial of compensation due to falsely elevated ethanol levels.<h4>2. Materials and Methods</h4><h5>2.4. Apparatus</h5>A <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=2010">Shimadzu GC-2010</a> Plus AF IVD system (Kyoto, Japan), fitted with an advanced flow controller (AFC), a split/splitless (SPL) inlet, and two flame ionization detectors (FID), was employed. Samples were processed and introduced via a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=HS-20">Shimadzu HS-20 static headspace autosampler</a> (Kyoto, Japan), with transfer to the GC through a single SPL inlet. The HS effluent was split equally (1:1) using a SilFlow® microfluidic platform (SHI-980-10593, Trajan, Ringwood, VIC, Australia) and directed onto two capillary columns: <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=50&amp;search=Zebron-BAC1">Zebron-BAC1</a> (30 m × 0.32 mm i.d., 1.8 μm film; Phenomenex, Torrance, CA, USA) and Zebron-BAC2 (30 m × 0.32 mm i.d., 1.2 μm film; Phenomenex, Torrance, CA, USA). Each column fed an independent FID channel, allowing concurrent acquisition from both separations. Headspace settings and chromatographic conditions for alcohol congener analysis followed those reported previously in [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B8-jox-16-00080">8</a>].<h4>3. Results</h4>Validation results are shown in <a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#table_body_display_jox-16-00080-t002">Table 2</a>. All presented values fall within the acceptable range for toxicological analysis of biological materials, in accordance with the recommendations of the German Society of Toxicological and Forensic Chemistry (GTFCh) [<a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#B10-jox-16-00080">10</a>]. Quality-control samples were prepared at three concentrations (low, medium, and high relative to the calibration range) by spiking blank samples. Relative error (RE) values within ±15% and precision expressed as relative standard deviation (RSD) ≤ 15% were considered acceptable, in accordance with GTFCh recommendations. The method, developed in 2019, has been subjected to international proficiency testing for ETB Ethanol in blood (ARVECON) and has consistently achieved positive results in each test. Additionally, the developed method for the determination of ethyl alcohol in blood was evaluated and achieved positive results in other proficiency tests, namely: the AXIO LGC Proficiency Testing Scheme in Drugs in blood Quantitative analyte selection, PT-TX-BLD (accreditation ISO/IEC 17043) (LGC Group Limited, Guildford, UK). Furthermore, the HS-GC-FID/FID method has been successfully implemented for routine toxicological analysis in our laboratory during the past 6 years.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/J_Xenobiot_2026_16_3_80_Table_2_Validation_results_for_six_quantified_volatile_compounds_methanol_ethanol_acetone_isopropanol_n_propanol_and_n_butanol_64ddd30e8d.jpg" alt="J. Xenobiot. 2026, 16(3), 80: Table 2. Validation results for six quantified volatile compounds: methanol, ethanol, acetone, isopropanol, n-propanol, and n-butanol. " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_J_Xenobiot_2026_16_3_80_Table_2_Validation_results_for_six_quantified_volatile_compounds_methanol_ethanol_acetone_isopropanol_n_propanol_and_n_butanol_64ddd30e8d.jpg 180w," sizes="100vw" width="1238" height="1073">Chromatograms of all compounds analyzed using the presented method, collected on two columns (Zebron ZB-BAC1 and Zebron ZB-BAC2), are shown in <a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#fig_body_display_jox-16-00080-f001">Figure 1</a>. During routine toxicological examinations, we analyzed various biological fluids, including standard matrices such as whole blood, serum, plasma, vitreous humor, and urine, as well as less commonly studied matrices such as bile, putrefaction fluid, and gastric contents.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/J_Xenobiot_2026_16_3_80_Figure_1_Chromatograms_of_ISTD_and_LOQ_of_volatile_compounds_obtained_from_two_columns_3826b6b870.jpg" alt="J. Xenobiot. 2026, 16(3), 80: Figure 1. Chromatograms of ISTD and LOQ of volatile compounds obtained from two columns (Zebron ZB-BAC1 and Zebron ZB-BAC2) and two flame ionization detectors. The retention time of tert-butanol (ISTD) on the first column was 2.848, and on the second it was 3.131. " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_J_Xenobiot_2026_16_3_80_Figure_1_Chromatograms_of_ISTD_and_LOQ_of_volatile_compounds_obtained_from_two_columns_3826b6b870.jpg 236w," sizes="100vw" width="1600" height="1056">Chromatograms from representative authentic cases are shown in <a target="_blank" rel="noopener noreferrer" href="https://www.mdpi.com/2039-4713/16/3/80#fig_body_display_jox-16-00080-f002">Figure 2</a>, including putrefaction fluid (containing 0.4‰ of ethanol) compared with a standard whole blood sample containing 1.38‰ ethanol.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/J_Xenobiot_2026_16_3_80_Figure_2_A_Chromatograms_of_putrefaction_fluid_with_ethanol_concentration_of_0_4_B_chromatograms_of_antemortem_blood_sample_with_ethanol_concentration_of_1_38_fe782ce3d1.jpg" alt="J. Xenobiot. 2026, 16(3), 80: Figure 2. (A) Chromatograms of putrefaction fluid (with ethanol concentration of 0.4‰); (B) chromatograms of antemortem blood sample (with ethanol concentration of 1.38‰). Results were provided for both columns: Zebron ZB-BAC1 and Zebron ZB-BAC2." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_J_Xenobiot_2026_16_3_80_Figure_2_A_Chromatograms_of_putrefaction_fluid_with_ethanol_concentration_of_0_4_B_chromatograms_of_antemortem_blood_sample_with_ethanol_concentration_of_1_38_fe782ce3d1.jpg 245w," sizes="100vw" width="1600" height="453"><h4>5. Conclusions</h4>The findings presented in this study demonstrate that reliable forensic determination of ethanol and other volatile compounds requires a comprehensive analytical strategy that extends beyond routine instrumental analysis. Despite the long-standing use of alcohol determinations in forensic practice, significant methodological limitations persist, particularly with respect to selectivity, internal standard selection, and control of pre-analytical and analytical variables. Based on a critical evaluation of currently published methods and supported by experimental evidence and authentic forensic casework, several key methodological principles emerge as essential for ensuring the evidential reliability of ethanol analysis in forensic toxicology. These principles are summarized below:<div><ul><li>Using two columns with different polarities combined with two detectors.</li><li>Avoiding internal standards such as n-propanol, n-butanol, and other substances that are formed postmortem in forensic investigations.</li><li>Utilizing tert-butanol as an internal standard in forensic toxicological practice.</li><li>Analysis of quality-control (QC) concentrations defined by law for DUI threshold limits, with verification that precision and accuracy remain within acceptable ranges.</li><li>Ensuring that sample preparation is performed in facilities free from exposure to airborne organic solvent vapors, particularly methanol and ACN (which are routinely used for protein precipitation in other toxicological analyses).</li><li>Preparation of analytical batches including two replicates of each sample, analyzed in a forward- and reverse-order sequence (e.g., samples 1–5 followed by 5–1) to verify analytical consistency.</li><li>Verification of internal standards and blank samples in each batch to ensure the absence of contamination during the pre-analytical phase.</li><li>Ensuring compliance with the acceptance criterion of a maximum 5% deviation between results, based on four measurements per sample.</li><li>Careful chromatographic evaluation and critical assessment of peak shape, symmetry, and resolution to minimize the risk of undetected interferences, particularly when using detectors such as FID, where retention time is the sole discriminating parameter.</li><li>Routine performance of independent proficiency tests to assess whether the method meets required accuracy and precision standards.</li><li>Biological fluids intended for forensic toxicology testing should be collected in tubes containing sodium fluoride (NaF) and stored under controlled conditions in a refrigerator maintained at 2–8 °C.</li></ul></div></div>

Dual-Column HS-GC-FID/FID Method for In-Depth Analysis of Low-Molecular-Weight Volatile Alcohols in Postmortem Biological Material

In the week of June 29, the following webinars await you in the field of gas / solid phase and especially Raman, FTIR, GC and GC/MS.<blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars">👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</a></h4>👉 Search and filter in the largest global database with over 5 500 GC, LC, MS and spectroscopy webinars.</blockquote><h5>1. Metrohm: Simplifying Through-Container Testing with Raman Spectroscopy in the Pharmaceutical Industry</h5><ul><li>Mo, 29.6.2026 15:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6308">Registration</a></li></ul>In this webinar, we will demonstrate a more robust and practical alternative to SORS for see-through Raman analysis.<h5>2. SelectScience: End-to-end PAT: Connecting advanced analytics and data across the bioprocess lifecycle</h5><ul><li>Mo, 29.6.2026 16:00 CEST</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/6307">Registration</a></li></ul>Learn how integrated PAT strategies combining NMR, Raman, IR, and digital workflows enable continuous process understanding, smoother tech transfer, and QbD from development to GMP manufacturing.

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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.

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.<h3>Key features</h3><ul><li>Reverse Fill-Flush (RFF) modulation for true comprehensive GC×GC with complete analyte transfer</li><li>Novel chromatography splitter with two channels of pressure assistance</li><li>Designed for high flows required for RFF modulation (≈20 mL/min)</li><li>Constant MS/FID split ratio maintained throughout the entire run, including oven temperature ramps</li></ul><h3>ChromaTOF makes modulation simple</h3>Paradigm eliminates complex offline flow calculations. Integrated <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41">ChromaTOF® software</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.<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"><h3>A shift forward in chromatographic analyses</h3>The Shift Flow Splitter 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.<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"><h3>Software-optimized detector performance</h3>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.<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">

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.

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.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 LECO—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.<h3>Key Benefits</h3><ul><li>Enhanced separation power for highly complex mixtures</li><li>Reduced noise and bias error compared to conventional GC-FID</li><li>Integrated <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41">ChromaTOF-based software</a> for acquisition, processing, classification, and reporting in one environment</li><li>Classification tools that simplify component identification</li><li>Cryogen-free modulation option eliminates the need for liquid nitrogen dewars</li></ul><h3>Theory of Operation</h3>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.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 50 ms—while maintaining accurate quantitation.<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"><h3>Thermal Modulation</h3>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 dual-stage, quad-jet thermal modulator positioned between the two columns. This design enables on-column cryo-focusing, dramatically improving peak detectability and resolving power, and delivering an order-of-magnitude improvement in signal-to-noise.For laboratories seeking lower operating costs and simplified workflows, a consumable-free thermal modulator (no liquid nitrogen) is available. This option maintains excellent performance for moderately volatile compounds while eliminating cryogen handling.<h3>Modulators and Instrument Options</h3><ul><li>Thermal modulator choices:<ul><li>Liquid-nitrogen-cooled thermal modulator</li><li>Consumable-free thermal modulator</li></ul></li><li>Optional inlets: S/SL, PTV, and MMI</li></ul>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.

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.

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.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.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ee943ea0acb34a8d9c5b72e7ace10666/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="957" height="523"><h4>Theory of Operation: Diverting Flow</h4>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.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/508b477dd1604d15855f26d786d5b1e4/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="1026" height="488">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.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/6796d4581c894291b9fab0088753cb8b/obrazek_l.webp" alt="LECO GCxGC FLUX flow modulator" width="918" height="545">

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.

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

Products from category Advanced technologies from LECO distributed by LECO Instrumente Plzeň - page 1

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