<h3><strong>How Deconvolution Output Files Support Library Searching, Method Validation, and Sample Comparison</strong></h3><p>Electron ionization (EI) GC-MS library searching has traditionally been viewed as a straightforward process: acquire a chromatogram, search spectra against a library, and identify compounds. However, modern NIST software performs a much more sophisticated workflow behind the scenes.</p><p>During processing, NIST creates an <strong>Identification Folder</strong> containing a collection of intermediate files that document every stage of chromatographic interpretation—from the original total ion chromatogram through component detection, spectral deconvolution, and final library searching. Although most users never open these files, they provide valuable insight into how identifications are generated and may even serve as the foundation for advanced comparison workflows.</p><blockquote><p class="cke-user_style-important"><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/paper/33364"><strong>You can download PDF Handout for this guide HERE</strong></a></p></blockquote><h3><strong>Why Does NIST Generate These Files?</strong></h3><p>When processing low-resolution EI GC-MS data, the software performs much more than simple spectrum matching.</p><p>Instead, it follows a sequential workflow:</p><ul><li>Raw chromatographic data acquisition</li><li>Detection of chromatographic components</li><li>Separation (deconvolution) of overlapping spectra</li><li>Generation of one clean spectrum for each chemical component</li><li>Library searching against the NIST database</li><li>Reporting of final identifications</li></ul><p>Rather than storing only the final results, NIST saves intermediate processing files that document each stage of the workflow. Together, these files form a complete processing record and improve both transparency and reproducibility.</p><h3><strong>The Low-Resolution EI GC-MS Processing Workflow</strong></h3><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/James_Little_The_Low_Resolution_EI_GC_MS_Processing_Workflow_0bc2c2b96f.jpg" alt="James Little: The Low-Resolution EI GC-MS Processing Workflow" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_James_Little_The_Low_Resolution_EI_GC_MS_Processing_Workflow_0bc2c2b96f.jpg 108w," sizes="100vw" width="430" height="622"></p><p>Additional files (.RUN and .LOG) preserve processing parameters and document every computational step performed during analysis.</p><h3><strong>Understanding Each File</strong></h3><h4><strong>1. .TIC – Total Ion Chromatogram</strong></h4><p>The <strong>TIC file</strong> contains the complete chromatographic signal collected during the GC-MS analysis.</p><p>It represents the familiar chromatogram displayed in the software interface and serves as the starting point for all subsequent processing.</p><h5><strong>Purpose</strong></h5><ul><li>Stores the raw chromatographic signal</li><li>Displays detector response versus retention time</li><li>Provides the visual overview of the analysis</li></ul><p>Although essential for evaluating chromatography, the TIC alone does not distinguish overlapping compounds. That task is handled during deconvolution.</p><h4><strong>2. .ELU – Component Detection</strong></h4><p>Once the chromatogram has been acquired, NIST identifies potential chromatographic components.</p><p>The <strong>ELU file</strong> records this information.</p><p>Typical information includes:</p><ul><li>Peak start and end times</li><li>Peak apex positions</li><li>Elution profiles</li><li>Grouped ion traces</li></ul><p>This stage determines where individual compounds are likely present before spectral deconvolution begins.</p><h4><strong>3. .FIN – Deconvoluted Spectra</strong></h4><p>The <strong>FIN file</strong> is arguably the most important intermediate product.</p><p>Rather than storing every acquired scan, NIST creates one clean spectrum for each resolved chromatographic component.</p><p>Each spectrum has:</p><ul><li>Reduced interference from co-eluting compounds</li><li>Cleaner fragment ion distributions</li><li>Improved suitability for library searching</li></ul><p>These spectra become the actual inputs used during library matching.</p><h4><strong>4. .TSV – Tabulated Results</strong></h4><p>The <strong>TSV file</strong> contains the processed results in a tab-delimited format suitable for export and further analysis.</p><p>Typical contents include:</p><ul><li>Retention times</li><li>Compound identifications</li><li>Match factors</li><li>Peak intensities</li><li>Library search results</li></ul><p>Because the information is already organized into tables, this file is particularly useful for reporting and external data analysis.</p><h4><strong>5. .RUN – Processing Parameters</strong></h4><p>The <strong>RUN file</strong> documents the analytical method used during processing.</p><p>Typical information includes:</p><ul><li>Deconvolution settings</li><li>Peak detection thresholds</li><li>Library search options</li><li>Processing parameters</li></ul><p>Maintaining these settings is essential for reproducible analyses and consistent comparison between datasets.</p><h4><strong>6. .LOG – Processing Record</strong></h4><p>The <strong>LOG file</strong> serves as the computational audit trail.</p><p>It records:</p><ul><li>Processing activity</li><li>Number of spectra analyzed</li><li>Library search operations</li><li>Timing information</li></ul><p>In the example shown in the presentation, the log indicates that:</p><ul><li>91 spectra were processed</li><li>Approximately 178,000 library comparisons were performed</li></ul><p>This confirms successful completion of both deconvolution and library searching.</p><h3><strong>A Key Concept: NIST Does Not Search Every Scan</strong></h3><p>One of the most important insights presented is that NIST does <strong>not</strong> perform library searches on every individual mass spectrum acquired during a GC-MS run.</p><p>Instead, the software first performs spectral deconvolution to isolate chemically meaningful components.</p><p>Only these cleaned component spectra are submitted for library searching.</p><p>This dramatically reduces computational complexity while simultaneously improving identification accuracy by minimizing interference from overlapping chromatographic peaks.</p><h3><strong>Can These Files Be Used for Sample Comparison?</strong></h3><p>Beyond routine identification, the presentation highlights an interesting possibility: using the generated output files for comparative analyses between samples.</p><p>Among the available files, the <strong>TSV file</strong> is the most practical starting point because it already contains structured analytical results.</p><p>Potential comparisons include:</p><ul><li>Compounds present in one sample but absent in another</li><li>Relative peak intensity differences</li><li>Changes in compound abundance</li><li>New or missing deconvoluted components</li><li>Differences in library match scores</li></ul><p>For more advanced investigations:</p><ul><li>FIN files enable direct comparison of deconvoluted spectra.</li><li>ELU files allow comparison of chromatographic behavior and peak shapes.</li><li>TIC files provide an overall chromatographic overview but are less suitable for compound-level comparisons.</li></ul><h3><strong>Opportunities for Advanced Data Analysis</strong></h3><p>Because these files contain structured intermediate processing data, they may also support custom computational workflows outside the NIST environment.</p><p>Possible applications include:</p><ul><li>Principal Component Analysis (PCA)</li><li>Batch quality control</li><li>Good vs. bad sample classification</li><li>Manufacturing process monitoring</li><li>Trend analysis across multiple GC-MS runs</li><li>Custom statistical or machine learning workflows</li></ul><p>Although NIST itself does not perform these analyses, the exported files provide a valuable foundation for external software and user-developed applications.</p><h3><strong>Best Practices</strong></h3><p>When working with NIST Identification Folder files:</p><ul><li>Use the <strong>TIC</strong> file for evaluating chromatographic performance.</li><li>Examine the <strong>ELU</strong> file to understand component detection.</li><li>Rely on the <strong>FIN</strong> file for studying deconvoluted spectra.</li><li>Use the <strong>TSV</strong> file for reporting, exporting, and comparative studies.</li><li>Preserve the <strong>RUN</strong> file to ensure reproducibility.</li><li>Review the <strong>LOG</strong> file whenever processing quality needs verification.</li></ul><p>Together, these files provide complete documentation of the identification workflow and offer far more information than the final library search results alone.</p><h3><strong>Conclusion</strong></h3><p>The Identification Folder generated during NIST low-resolution EI GC-MS processing is much more than a collection of temporary files. It represents a comprehensive record of the entire analytical workflow, from raw chromatographic data through deconvolution and library searching. Understanding the role of each file helps users interpret results with greater confidence, troubleshoot processing steps, and explore advanced applications such as sample comparison, chemometric analysis, and custom data processing workflows. Rather than being hidden implementation details, these files can become valuable resources for improving transparency, reproducibility, and analytical insight in GC-MS data analysis.</p>

Raw Data Files for EI Low Resolution in the Identifications Folder

<p><strong>Scientific conferences are defined not only by the quality of the research presented but also by the expertise and vision of their invited speakers. RAFA 2026 brings together internationally recognized scientists from academia, industry, and regulatory organizations to address some of today's most pressing challenges in food analysis and food safety. Their lectures will explore cutting-edge analytical techniques, emerging contaminants, food authenticity, artificial intelligence, high-resolution mass spectrometry, allergen risk assessment, PFAS, microplastics, mycotoxins, and many other topics shaping the future of food analysis. This overview introduces the distinguished invited speakers and the scientific highlights they will present at RAFA 2026.</strong></p><h3><strong>Registration</strong></h3><blockquote><p class="cke-user_style-important"><strong>👉</strong><a target="_blank" rel="noopener noreferrer" href="https://rafa.easyevent.eu/tickets/"><strong>Register to attend RAFA 2026!</strong></a></p></blockquote><h4><strong>Registration Fees</strong></h4><ul><li><strong>Regular registration (Until 30 September, 2026):</strong> € 855</li><li><strong>Late registration (From 1 October, 2026):</strong> € 955</li><li><strong>Student rate* (From 1 July, 2026):</strong> € 605</li></ul><p><i>* The proof of student status (e.g. copy of a student identify card) is requested as an attachment of the registration form.</i></p><h5><strong>The regular registration fee will include:</strong></h5><ul><li>Attendance at all scientific sessions, workshops, seminars, vendor seminars and other satellite events</li><li>Access to the poster and exhibition area</li><li>Conference kit (name badge, conference bag, conference documents, certificate of participation, certificate of presentation on request)</li><li>Final programme</li><li>E-Book of Abstracts</li><li>Coffee breaks</li><li>Buffet luncheons</li><li>Welcome drink</li></ul><p>In the registration form you can r<strong>egister free of charge for the welcome drink</strong> and you can also order <strong>ticket(s) for the conference dinner (€ 85).</strong></p><p><i>Please note that your registration is firm when your payment has been received.</i></p><h3><strong>Abstract submission</strong></h3><blockquote><p class="cke-user_style-important"><strong>👉</strong><a target="_blank" rel="noopener noreferrer" href="https://rafa.easyevent.eu/tickets/"><strong>Submit your ABSTRACT HERE!</strong></a></p><p>In order to submit an abstract, you must <strong>first register to attend RAFA 2026</strong>. <strong>After registration</strong> you will receive an <strong>access to the Member section </strong>where you can <strong>submit your abstract(s).</strong></p></blockquote><p>&nbsp;After successful submission of your abstract you will receive an automatic confirmation of receipt of submitted abstract via e-mail. If it will not be delivered within a few minutes after submission of your abstract please check at first your spam box-mail and then contact us at <strong>RAFA2026@vscht.cz</strong>.</p><h4><strong>Important notice:</strong></h4><blockquote><p><strong>1 registered participant can submit no more than 2 abstracts.</strong></p></blockquote><p>To apply for a young scientist’s oral presentation, as an indication please respect the rule that you should be born in 1991 or later.</p><p>The <strong>text of the abstract </strong>should be<strong> limited to 3000 characters including spaces</strong>. Tables and pictures are not allowed.</p><h3><strong>Program</strong></h3><h4><strong>Invited Speakers</strong></h4><h5><strong>It takes a small step to fake food but a giant leap to authenticate</strong></h5><ul><li>Nicolai Zederkopff Ballin from Danish Veterinary, Food, Agriculture and Fisheries Agency, Glostrup, Denmark.</li></ul><p>It takes a small step to fake food but a giant leap to authenticate”: Exploring unresolved issues in food authentication. Food authentication includes not just analytical chemistry, but also nomenclature, validation procedures and reporting of results. These aspects have attracted increasing focus, but setting limits in food authentication has been largely absent. It is therefore time to discuss how to set maximum tolerable levels to enable consistent and comparable results in food authentication.</p><h5><strong>Unravelling the mysteries of modified mycotoxins</strong></h5><ul><li>Franz Berthiller from BOKU University, Vienna, Austria</li></ul><p>Modified mycotoxins are altered forms of mycotoxins, mainly formed by living plants on the field. They are not regulated, yet may contribute to toxicity. The presentations focuses on metabolites of fumonisin B1 and ochratoxin A, formed by maize plants.</p><h5><strong>From bitter to better: Fixing off-flavors in plant proteins</strong></h5><ul><li>Corinna Dawid from Leibniz Institute for Food Systems Biology at the Technical University of Munich, Freising, Germany</li></ul><p>Uncovering the chemistry behind flavor: the presentation explores how Sensomics and NMR interaction studies reveal the complex interplay between aroma compounds, taste perception, and the polymer matrix in wine.</p><h5><strong>Imaging food: the power and the limits of seeing molecules in food</strong></h5><ul><li>Laura Righetti from Wageningen University &amp; Research, Wageningen, the Netherlands</li></ul><p>Imaging techniques enable ‘seeing’ molecules in food and elucidating mechanisms of accumulation and transformation, e.g. during processing. However, their application to food and contaminants remains limited. This talk discusses both instrumental constraints and future opportunities.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/RAFA_Laura_Righetti_e7bdda9942.jpg" alt="RAFA: Laura Righetti" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_RAFA_Laura_Righetti_e7bdda9942.jpg 157w," sizes="100vw" width="900" height="895"></p><h5><strong>Analysis of critical vitamins: novel structures and novel sources</strong></h5><ul><li>Michael Rychlik Lab from Technical University of Munich, Freising, Germany</li></ul><p>Growing population and dietary shifts lead to inadequate intake of folate, B6, and B12. The presentation introduces novel analytical methods (stable isotope dilution assays), identifies new sources, and assesses risks of certain dietary patterns.</p><h5><strong>Sample-to-solution approaches for natural toxin analysis at the point of need</strong></h5><ul><li>Gert Salentijn from Wageningen University &amp; Research, Wageningen, the Netherlands</li></ul><p>Taking analysis out of the lab is not trivial. Going beyond merely translating procedures from the lab to an out-of-lab setting, it requires a fundamentally different perspective on how we develop and deploy the tools to provide information at the point-of-need. In this, both the envisioned test, as well as the envisioned user are critical, and all the steps, from sample to solution, need to be considered.</p><h5><strong>EFSA’s rapid risk assessment of cereulide in infants</strong></h5><ul><li>Hans Steinkellner from European Food Safety Authority, Parma, Italy</li></ul><p>The EU has established procedures for rapid risk assessment in urgent situations. EFSA’s assessment of cereulide in infants demonstrated its ability to provide robust scientific support within a short timeframe during a crisis.</p><h5><strong>Comprehensive strategies to unmask masked mycotoxins: from food matrix to gut microbiota</strong></h5><ul><li>Milena Stranska from University of Chemistry and Technology Prague, Prague, Czechia</li></ul><p>The lecture will address non-extractable modified mycotoxins and their biological relevance. Bioaccessibility will be assessed using in vitro digestion models with diverse fecal microbiota (toddlers, children, adults) and bioavailability using Caco-2-based intestinal models. High-resolution mass spectrometry will reveal biotransformation pathways and cellular metabolism of free and modified mycotoxins.</p><h5><strong>Food allergen risk assessment: Past, present, future</strong></h5><ul><li>Ben Remington from Remington Consulting Group B.V., Utrecht, the Netherlands &amp; University of Nebraska, USA</li></ul><p>Food allergy and allergen management are global public health issues, and consumer protection depends on transparent and trustworthy labelling. While 30 years of scientific advances show that low level exposures, or reference doses, are unlikely to trigger reactions in most allergic individuals, harmonized and globally aligned regulations are still needed to promote consistent allergen risk assessment and labelling decisions. This presentation will discuss the landscape of allergen risk assessment, global policy developments, current research and future needs in the area.</p><h5><strong>Unmasking hidden adulteration in honey: Strategies for detecting and characterizing honeys produced from sugar-fed colonies</strong></h5><ul><li>Oscar Nuñez Burcio from University of Barcelona, Barcelona, Spain</li></ul><p>From hive to jar, not all honey tells the same story. This presentation addresses hidden adulteration associated with sugar-fed bee colonies, highlighting implications for authenticity, production practices, and the need for a more precise characterization of honey to ensure consumer trust.</p><h5><strong>Analytical and toxicological methods for safety of food contact materials</strong></h5><ul><li>Erich Leitner from Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Graz, Austria</li></ul><p>Food packaging plays a critical role in protecting and preserving food throughout the supply chain. All packaging materials intended to come into contact with food must comply with strict EU safety rules. Due to increased complexity of packaging solutions, lowering legal limits and increasing numbers of target compounds, we also have to adapt the strategies used to verify and guarantee the safety of these materials.</p><h5><strong>Data-driven strategies to reduce complexity in non-target HRMS analysis of food samples</strong></h5><ul><li>Anneli Kruve from Stockholm University, Stockholm, Sweden</li></ul><p>LC/HRMS based non-target screening can detect hundreds to thousands of chemical features in complex food and environmental samples. Investigating all of these in detail is practically impossible, so which ones to focus on? Novel computational tools developed in computational mass spectrometry allow predicting the toxicity and concentration of the detected chemical features even if these have not yet been fully structurally elucidated. Combining these predictions enables us to focus on the chemical features possessing high risk.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/RAFA_Anneli_Kruve_5119012e5d.jpg" alt="RAFA: Anneli Kruve" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_RAFA_Anneli_Kruve_5119012e5d.jpg 155w," sizes="100vw" width="899" height="900"></p><h5><strong>Role of AI in the identification of emerging food systems risks</strong></h5><ul><li>Ákos Bernard Jóźwiak from Syreon Research Institute, Budapest, Hungary</li></ul><p>AI-assisted evidence synthesis – spanning curated scientific evidence, exposome data, and network analysis – is the backbone of next-generation emerging chemical food safety risk identification, enabling earlier signals and more resilient surveillance systems.</p><h5><strong>Challenges of microplastics analysis in the context of food safety</strong></h5><ul><li>Dorte Herzke from Norwegian Institute of Public Health, Oslo, Norway</li></ul><p>Food and food packaging are major sources of micro- and nanoplastic exposure. Plastics used in processing, storage, and packaging can release particles through heat, abrasion, and degradation. Small particles below 2 µm may cross gut barriers and carry chemicals, highlighting the need for robust and sensitive measurement methods.</p><h5><strong>Never-ending analytical challenges in PFAS analysis of food</strong></h5><ul><li>Darina Dvořáková from University of Chemistry and Technology Prague, Prague, Czechia</li></ul><p>Exploring and monitoring PFAS in food requires advanced strategies. Combining targeted, suspect, and non-target HRMS analysis, determination of total fluorine and sum parameters, and novel sensors provides new insights into PFAS occurrence and supports food safety monitoring.</p><h5><strong>An overview of the latest scientific knowledge on process contaminants in food for appropriate risk management measures</strong></h5><ul><li>Thierry Delatour from Nestlé Research, Lausanne, Switzerland.</li></ul><p>Recent scientific findings related to acrylamide and furans formation, occurrence and analytical methods in food provide important insights for risk management.</p>

Invited Speakers at RAFA 2026 Symposium

<p><strong>Our Library never stops expanding. What are the most recent contributions to LabRulezGCMS Library in the week of 13th July 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 posters by <strong>Agilent Technologies / ASMS,&nbsp;</strong> <strong>MDCW / William &amp; Mary, </strong>and<strong> Thermo Fisher Scientific</strong> <strong>/ ASMS </strong>and technical note by <strong>Shimadzu!</strong></p><h3><strong>1. Agilent Technologies / ASMS: Comprehensive PFAS Analysis in Textiles Using Triple Quadrupole GC/MS and LC/MS Workflows</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/po_pfas_textiles_gc_tq_lc_tq_wp_414_asms_2026_en_agilent_a1d50ab96c.pdf"><strong>Full PDF for download</strong></a></li></ul><section><div><div><div><div><div><div><p>Per- and polyfluoroalkyl substances (PFAS) are widely used in textiles to provide water-, stain-, and oil-repellent functionality. Increasing evidence of environmental and human-health risks has led to heightened global regulatory pressure, including REACH/POPs restrictions, and strengthened requirements from industry frameworks such as ZDHC, OEKO-TEX®, AFIRM, and Bluesign. These initiatives demand highly sensitive, reliable, and standardized analytical workflows capable of quantifying both volatile and non-volatile PFAS in diverse textile matrices. This study demonstrates end-to-end PFAS solutions aligned with EN 17681-1:2025, comprising heat- and ultrasound-assisted (HUA) extraction followed by GC/TQ and LC/TQ determination of volatile and non-volatile PFAS, respectively. The workflow enables robust quantification of a comprehensive PFAS panel in T-shirts, waterproof shorts, and socks.</p><h4><strong>Experimental</strong></h4><h5><strong>Instrumentation&nbsp;</strong></h5><p>A dual-platform analytical approach combining GC/TQ and LC/TQ systems was used to quantify over 100 PFAS across 14 chemical classes (Figure 1). More than 30 volatile PFAS were analyzed using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=8890"><strong>Agilent 8890 GC</strong></a> coupled to a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=7010D"><strong>7010D TQ</strong></a> and a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-624"><strong>DB-624 column</strong></a>. Over 70 non-volatile PFAS were determined using an <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=10&amp;search=6475"><strong>Agilent 6475 LC/TQ</strong></a> paired with a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=10&amp;search=1290+infinity+III"><strong>1290 Infinity III UHPLC </strong></a>and a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=10&amp;search=ZORBAX+RRHD+Eclipse+Plus+C18"><strong>ZORBAX RRHD Eclipse Plus C18</strong></a> column.</p><h4><strong>Conclusions</strong></h4><ul><li>A dual-platform approach deploys Agilent 8890 GC coupled with 7010D TQ and Agilent 1290 Infinity III LC with 6475A TQ system for volatile and non-volatile PFAS in textiles.&nbsp;</li><li>Fast and simplified workflow: Utilizes a streamlined protocol based on EN 17681-1:2025. The method enhances lab productivity by eliminating tedious evaporation and reconstitution steps.&nbsp;</li><li>Regulatory compliance: Effectively addresses increasing textile industry focus on PFAS monitoring and supports compliance with various regulatory standards and limit requirements for PFAS detection in textiles.</li></ul><h3><strong>2. MDCW / William &amp; Mary: The Effect Of Using Low-Bleed Columns In The First Dimension For Comprehensive Two-Dimensional Gas Chromatographic Analyses</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Webb_MDCW_Poster_2026_1_5657991949.pdf"><strong>Full PDF for download</strong></a></li></ul><section><div><div><div><div><div><div><p>In gas chromatography, the presence of column bleed impacts peak data quality. As siloxanebased stationary phase components fragment, they release bleed artifacts into the mass spectrometer (MS), producing interference and decreasing signal-to-noise ratios (S/N) of analytes. <sup>1</sup> When using comprehensive twodimensional gas chromatography (GC×GC), a secondary column with an orthogonal stationary phase is used in providing improved separation between column bleed and analytes. However, it also introduces more stationary phase that can be degraded to produce more bleed artifacts.</p><p>The goal of this research was to define how replacing the primary column in a GC×GC-MS system impacts the resulting S/N and analyte identification quality, in order to clarify how column bleed impacts analytes that appear to be chromatographically resolved from column artifacts in GC×GC output. This will demonstrate the advantage that low-bleed columns can provide for future analyses.</p><h5><strong>Methods</strong></h5><p>Samples analyzed were the Century Mix2 , containing approximately 100 different analytes within different classes (i.e. Century Mix2) and a 52- component Indoor Air Standard. Both were assessed using a 5% phenyl/95% dimethylsiloxane standard column in the first dimension and a (50%-phenyl)-methylpolysiloxane standard column in the second dimension. Samples were then reanalyzed with a low-bleed column replacement in the first dimension.</p><p>Analysis of the samples was performed using the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/37"><strong>Pegasus BT4D GC×GCTOFMS</strong></a> with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/44"><strong>quad-jet dual-stage cryogenic modulator</strong></a><strong> </strong>(LECO Corporation). <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41"><strong>ChromaTOF software</strong></a><strong> </strong>(LECO Corporation) was used to analyze the chromatographic data.</p><h4><strong>Conclusions</strong></h4><p>This work demonstrated that samples run with the low-bleed first dimension column showed a reduction in the presence of column bleed components identified and maintained or improved the quantitative signal-to-noise ratios of components compared to the samples run on standard first dimension columns. This showed that that low concentration analytes were more reliably detected in the absence of column bleed, even when contour plots showed physically resolved components. In the future, this can be applied to improve the resolution of complex samples and increase analyte signal.</p><h3><strong>3. Shimadzu: Dimethyl carbonate as a green organic modifier in supercritical fluid extraction of pesticide residue analysis in apple samples</strong></h3><ul><li>Technical note</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/c190_e347_869b9e2ade.pdf"><strong>Full PDF for download</strong></a></li></ul><p>According to the Green Analytical Chemistry (GAC) principles[1], a highly promising strategy to minimize the side effects of analytical methods involves replacing potentially toxic solvents and/or obtained by non-renewable sources with more environmentally friendly alternatives. In this frame, dimethyl carbonate (DMC) is an environmentally friendly, non-corrosive, safe handling, and biodegradable chemical, extensively used in several application fields, such as pharmaceuticals, coatings, and lithium-ion battery electrolytes [2]. Additionally, instead of the historical use of toxic and corrosive phosgene as a carbonate source, simple and direct synthesis routes from carbon dioxide (CO2) have been proposed [3]. Thus, also falling within the “carbon capture and utilization” processes, ensuring the reduction of atmospheric CO2 concentration and its conversion into useful chemical products.&nbsp;</p><p>Firstly introduced in the second edition of the GlaxoSmithKline’s solvent selection guide, DMC has been included among the “few issues” solvents, along with water [4]. Thereafter, it has attracted widespread attention as a valuable chemical and/or solvent, and substantial research efforts have been made in the scientific community. Its potential as a green alternative to conventional solvents in both reversed-phase liquid chromatography [5–7] and supercritical fluid chromatography [8] has been explored. The extraction capabilities of DMC toward different target molecules have been also investigated. In 2022, Alfieri et al. optimized an ultrasoundassisted extraction of two lignans from Linum species [9]. The extraction performances of a panel of green solvents and two natural deep eutectic solvents (in combination with water in a solvent/water ratio of 80:20) were tested versus methanol and chloroform (used for comparison with published studies). The results showed that, in terms of purity and recovery, DMC was the optimal media for the 6-methoxypodophyllotoxin extraction. DMC has been also employed in an in-syringe extraction coupled to solid phase extraction to assess nicotine in environmental water and sportspersons’ urine samples [10]. Extracts enriched in oleanolic acid were obtained by solid-liquid extraction of grape pomace using DMC compared to other tested solvents (ethyl acetate, acetone, n-butanol) [11]. In addition to the highest obtained recovery value, the lowest co-extraction of other matrix components was also achieved.&nbsp;</p><p>Supercritical fluid extraction (SFE) represents a reliable alternative to conventional solvent-based extraction methods. Several advantages are provided when CO2 is employed as supercritical fluid due to its non-toxicity, non-flammability, abundancy, renewability (as a by-product of industrial processes, as fermentation or combustion), recyclability, and cost-effectiveness. Supercritical CO2 has a polarity similar to that of n-hexane; thus, the addition of a co-solvent is necessary for the extraction of polar molecules [12, 13].&nbsp;</p><p>This work aims to expand the use of DMC that, to the best of the author’s knowledge, is here firstly proposed as an organic modifier in SFE. The extraction efficiency and selectivity of DMC toward conventional solvents, such as acetonitrile (ACN) and bio-ethanol (EtOH) obtained from edible renewable feedstocks, has been evaluated for multi-residue analysis of pesticides (64 pesticides, representing diverse chemical classes, polarities, and molecular weights) in apple samples. Considering the sustainable and nontoxic nature of CO2 and DMC, the use of DMC in SFE represents a win-win combination. Thus, improving the overall sustainability and automation of the extraction process closely align with the GAC principles. Furthermore, in this research, always following the GAC principles, a low-pressure gas chromatography-tandem mass spectrometry (LP-GC-QqQMS) method was employed, allowing a greater sample loadability and a higher optimal linear velocity allowed by the vacuum conditions of the system, effectively reducing the analysis time at about 10 minutes [14, 15].</p><h4><strong>2. Materials and methods</strong></h4><h5><strong>2-3. Instrumentation</strong></h5><h5><strong>Low‑pressure gas chromatography triple quadrupole mass spectrometry&nbsp;</strong></h5><p>The LP-GC-QqQMS analyses were performed using a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GC-2010"><strong>GC-2010 Plus system</strong></a> (Shimadzu Corporation, Kyoto, Japan) coupled with a <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=8040"><strong>triple quadrupole mass spectrometer (TQ8040</strong></a>, Shimadzu). Injection was performed using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-20i"><strong>AOC-20i autosampler</strong></a><strong> </strong>and<strong> </strong>a split/splitless injector (injection temperature 280 °C) equipped with a focus liner (volume: 810 μL). The injection was performed in splitless mode (3 μL) using the high-pressure injection mode function (290 kPa for 0.5 min).&nbsp;</p><p>To avoid that sub-ambient pressure conditions reach the injector, an uncoated column (0.48 m × 0.1 mm ID) was installed before the separation column, a non-polar Equity-5 [poly(5% diphenyl/95% dimethyl siloxane)] of the following dimension: 5 m × 0.53 mm ID × 0.53 μm df. Both the columns were provided by Merck KGaA. The oven was temperature programmed as follows: 40 °C (2 min) to 320 °C raised at 30 °C min−1. Helium was used as carrier gas with an average constant linear velocity of 100 cm s−1 (into the separation column).&nbsp;</p><p>Electron ionization was performed at 70 eV. The interface and ion source temperatures were 320 and 280 ˚C, respectively. The collision gas was argon at a pressure of 200 kPa. The targeted analyses were carried out in the multiple reaction monitoring (MRM) acquisition mode (acquisition frequency: 3.3 Hz). To ensure univocal identification, two different MRM transitions (quantifier and qualifier) were monitored for each compound (Table S1). The SCAN analysis was performed with an acquisition frequency of 3.3 Hz and a mass range of 50–600 m/z. The GCMS Solution v.4.45 software (Shimadzu) was used for data collection and processing.</p><h4><strong>4. Conclusions&nbsp;</strong></h4><p>Under the optimized extraction conditions, the use of DMC as a co-solvent in SFE demonstrated promising performance in the analysis of pesticide residues in apple samples. The method achieved an average extraction yield of 85% across the 64 analyzed pesticides, spanning a broad range of chemical classes, polarities, and molecular weights. Notably, DMC provided cleaner extracts with significantly lower amounts of co-extracted matrix components compared to conventional solvents like ACN and EtOH. Despite the recovery for certain analytes being below 70%, the results remained within acceptable precision limits according to SANTE guidelines. Overall, DMC not only fulfills the analytical requirements for pesticide residue determination but also offers a greener, more sustainable alternative that supports enhanced instrument maintenance and aligns with the principles of GAC.</p><h3><strong>4. Thermo Fisher Scientific / ASMS: Improved detection capabilities for polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) using GC Orbitrap MS</strong></h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/po_004693_lsms_pcdd_fs_exploris_gc_efs_po004693_asms2026_na_en_68e4d9e8b3.pdf"><strong>Full PDF for download</strong></a></li></ul><p>Polychlorinated dibenzo-p-dioxins/furans (PCDD/F) analysis requires ultra-high sensitivity and selectivity due to their toxicity at trace levels. Regulatory compliance requires laboratories to adhere to strict analytical criteria (Figure 1). Through the integration of NVAEI source (NVAEI) with HRAM Thermo Scientific Orbitrap mass spectrometer, the <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/2419"><strong>Orbitrap Exploris GC S </strong></a>delivers mass resolution and accuracy that far exceed those required while delivering enhanced sensitivity required for pg/g (part per trillion (ppt)) detection within food and feed matrices.</p><h4><strong>Conclusions&nbsp;</strong></h4><p>Enhanced sensitivity of the NeverVent AEI ion source coupled to the Orbitrap Exploris GC S delivers accurate quantitation down to 2 fg/μL (10 fg on column) of TCDD while meeting analytical criteria required for Dioxin analysis compliance.&nbsp;</p><p>Response of 2 fg/μL (10 fg on column) of TCDD standard remained stable over a 185-injection sequence of food/feed extract, demonstrating robust performance of the NeverVent AEI at maintaining trace level sensitivity.&nbsp;</p><p>Good agreement in the analysis of food and feed extracts preformed by GC-HRMS magnetic sector demonstrates the Orbitrap Exploris GC S can deliver accurate quantitation at and below regulatory limits.</p></div></div></div></div></div></div></section></div></div></div></div></div></div></section>

News from LabRulezGCMS Library - Week 29, 2026

Article

Events

Academy

Video

Scientists

Software

Poster

RAFA provides an overview of contemporary trends in ANALYTICAL & BIOANALYTICAL STRATEGIES IN FOOD QUALITY AND SAFETY CONTROL and discusses CHALLENGES / NOVEL APPROACHES IN FOOD AND NATURAL PRODUCTS ANALYSIS.

Recent Advances in Food Analysis (RAFA)

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

LabRulez

My main interest is the identification of organic compounds by mass spectrometry in organic mixtures.

James Little/Mass Spec Interpretation Services

Metrohm

Milestone

<p><strong>Learn more about handheld Raman technologies and their effectiveness for raw material control in pharmaceutical manufacturing settings.</strong></p>
<p>The use of the NanoRam-1064 is highlighted as it can be used to overcome fluorescence and is able to identify many complex and colored materials often used in biopharmaceutical manufacturing.</p>
<blockquote>
<p><strong>Presenter:</strong> Katherine A. Bakeev, Ph.D. (B&amp;W Tek)</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Adam J. Hopkins, Ph.D. (Metrohm USA)</p>
</blockquote>


Raw Material Control Strategies

Learn more about handheld Raman technologies and their effectiveness for raw material control in pharmaceutical manufacturing settings.

Raw Material Control Strategies with handheld Raman

<p><strong>In this webinar, learn how accurate, reliable and portable screening tools can help detect substandard and counterfeit medicines.</strong></p>
<blockquote>
<p><strong>Presenter:</strong> Dr. Mustapha Hajjou (PQM, U.S. Pharmacopeial Convention)</p>
</blockquote>


Metrohm: Screening in post-marketing surveillance

Screening in post-marketing surveillance

In this webinar, learn how accurate, reliable and portable screening tools can help detect substandard and counterfeit medicines.

Medicines Quality Screening in post-marketing surveillance

<p><strong>This webinar discusses the official guidelines for the analysis of polyols by NIRS and the basic principles of NIRS and how this technology is implemented in the QC laboratory.</strong></p>
<p>In the practical part, Dr. Omar Sallouh, Head of Quality Assurance &amp; Process Engineering at Rampf Polymer Solutions GmbH &amp; Co. Kg will outline his first-hand experiences with polyol, isocyanates, and silicones analysis using near-infrared spectroscopy.</p>


Metrohm: Efficient QA/QC of polyols by NIRS – Theory and praxis

Efficient QA/QC of polyols by NIRS – Theory and praxis

The official guidelines for the analysis of polyols by NIRS and the basic principles of NIRS and how this technology is implemented in the QC laboratory.

<p><strong>This webinar hosted by the European Pharmaceutical Review together with Metrohm deals with how to implement near-infrared spectroscopy in pharmaceutical processes.</strong></p>


NIRS in pharma processes

How to implement near-infrared spectroscopy in pharmaceutical processes.

<p><strong>Learn more about reducing the cost of quality control using near-infrared spectroscopy. This webinar shows how Herbalife has implemented NIRS in their QC/QA workflows.</strong></p>


Optimized QC with NIRS

Learn more about reducing the cost of quality control using near-infrared spectroscopy.

<p><strong>Discover how NIRS can help you in the monitoring of polymer production. This webinar gives an introduction into the topic and provides some examples of applications in place at Cytec.</strong></p>


NIRS in polymer production

Discover how NIRS can help you in the monitoring of polymer production.

<p><strong>This webinar offers an overview of the possibilities of NIRS for the quantitative and qualitative analysis of personal care products, e.g., creams, hairspray, detergent ingredients, and soap, as implemented at Colgate Palmolive.</strong></p>


Personal care products analysis

Possibilities of NIRS for the quantitative and qualitative analysis of personal care products, e.g., creams, hairspray, detergent ingredients, and soap.

Personal care products analysis by NIRS

<p><strong>This webinar hosted by the European Pharmaceutical review together with Metrohm shows how near-infrared spectroscopy can be used as a PAT tool in the real-time monitoring of the moisture content in different types of dryers.</strong></p>


NIRS: Moisture in dryers

How near-infrared spectroscopy can be used as a PAT tool in the real-time monitoring of the moisture content in different types of dryers.

<p><strong>Learn how near-infrared spectroscopy can be used as a PAT tool from raw material identification to integrated process applications.</strong></p>


NIRS as a PAT tool

Learn how near-infrared spectroscopy can be used as a PAT tool from raw material identification to integrated process applications.

<p><strong>Sample preparation is a routine step in many analyses, but it’s often underestimated. Choosing the right sample preparation step is fundamental, as it can prevent contamination, improve accuracy, and minimize the risk of skewing the results. Despite that, most of the methods applied to fats and oils sample preparation are still tied to traditional, time- and solvent-consuming procedures. The complexity of the food matrices led to challenging sample preparation, for example, the time-consuming saponification. Over the years traditional techniques have been improved, but they are still relying on ancient technologies, so now laboratories are seeking new approaches to ensure fast, rugged, and reproducible analysis of food.</strong></p><p>Microwave assisted solvent extraction (MASE) and microwave assisted saponification (MAS) offer a reliable and efficient approach to sample preparation. Several processes can take advantages from microwave heating, reducing time and solvent consumption, enabling the lab to have a greener and more cost-effective approach. In this section some examples will be reported ranging from extraction of contaminants (MOAH and MOSH), to saponification and extraction of DAKs and sterols, to fatty acid methyl ester profile determination from foodstuff.</p><blockquote><p><strong>Speaker:</strong> Dr. Diego Carnaroglio, Business Development &amp; Application Manager at Milestone</p><p><strong>Speaker: </strong>Prof. Giorgia Purcaro, Gembloux, Agro-Bio Tech, University of Liège, Belgium</p><p><strong>Speaker: </strong>Dr. Roberto Boschini, Product Manager at Milestone</p></blockquote>

Milestone: Microwave-assisted solvent extraction: A powerful tool to tackle sample preparation challenges

Microwave-assisted solvent extraction: A powerful tool to tackle sample preparation challenges

Learn how microwave-assisted extraction and saponification improve fats and oils sample preparation, cutting time and solvents.