Scientists at IOCB Prague are uncovering new details of gene transcription. They have identified a previously unknown molecular mechanism by which the transcription of genetic information from deoxyribonucleic acid (DNA) into ribonucleic acid (RNA) can be initiated. The researchers focused on a specific class of molecules known as alarmones, which are found in cells across a wide range of organisms and whose levels often increase under conditions of cellular stress. The results were published in the prestigious scientific journal Nature Chemical Biology.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Hana Cahová, head of the Chemical Biology of Nucleic Acids research group." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Molecules of ribonucleic acid can carry a variety of chemical modifications at one end, known as caps. In eukaryotic organisms, including human cells, the best-known cap plays an important role in RNA stability and in regulating its subsequent fate. In recent years, however, it has become clear that alternative, non-canonical RNA caps also exist, although their formation and the mechanisms by which they are attached to RNA remain only partially understood. These include alarmone caps, formed by dinucleoside polyphosphate molecules, that protect cellular RNA at moments when the cell is under threat.In their study, <a target="_blank" rel="noopener noreferrer" href="https://cahova.group.uochb.cz/en">Dr. Hana Cahová</a> and colleagues examined bacterial RNA polymerase and investigated how this enzyme can initiate transcription using dinucleoside polyphosphates (NpNs) instead of the standard RNA building blocks. For the first time, the scientists described, at the atomic level, how RNA bearing an alarmone cap can be generated directly at the initiation of gene transcription. They also observed that NpNs bind through a different type of base pairing than is typically observed.The work was significantly shaped by Valentina Serianni from Hana Cahová’s team, who demonstrated the ability of dinucleoside polyphosphates to initiate gene transcription, and by Jana Škerlová, who focused on the structural analysis of RNA polymerase. Using cryogenic electron microscopy data, she showed how dinucleoside polyphosphate molecules bind within the active site of RNA polymerase – that is, the core of the enzyme where genetic information is transcribed. Together, their findings help to elucidate the processes that accompany the transcription of genetic information from DNA to RNA.Hana Cahová adds: “We’re describing something that truly occurs in cells and that we’re now able to observe directly at the level of individual molecules. This allows us to answer fundamental questions about cellular processes, such as how cells adapt to stress. RNA plays a central role in this, as it carries the cascade of information underlying any cellular response – for example, to threatening conditions caused by nutrient deprivation or temperature shock.”<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Tomáš Kouba, head of the Cryogenic Electron Microscopy core facility." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Cryogenic electron microscopy (cryo-EM) was central to the project. This part of the work was led by Dr. Tomáš Kouba, one of the authors of the study. “Cryogenic electron microscopy allows us to freeze biological molecules in a state very close to their natural form and then determine their three-dimensional structure. This makes it possible to look directly into the active centers of enzymes and observe their function down to the atomic level,” he explains.Last year, IOCB Prague opened a new <a target="_blank" rel="noopener noreferrer" href="https://cryoem.group.uochb.cz/en">cryo-EM center</a> that is unique within the Czech research environment. State-of-the-art cryogenic electron microscopes are housed in a specially designed building and enable the study of biological processes with exceptional structural precision.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg" alt="IOCB Prague: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: This work shows how NpnNs initiate bacterial transcription. Cryo-EM reveals how nucleobases pair with the template: one in canonical and one in reverse Watson–Crick mode, providing a structural basis for their function as non-canonical RNA caps." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg 245w," sizes="100vw" width="2000" height="1077"><blockquote><h4>The Original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41589-025-02134-5">Molecular insight into 5′ RNA capping with NpnNs by bacterial RNA polymerase</a></h4>Valentina M. Serianni, Jana Škerlová, Anna Knopp Dubánková, Anton Škríba, Hana Šváchová, Tereza Vučková, Anatolij Filimoněnko, Milan Fábry, Pavlína Řezáčová, Tomáš Kouba &amp; Hana Cahova&nbsp;Nat. Chem. Biol. 21 (2026)<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1038/s41589-025-02134-5">https://doi.org/10.1038/s41589-025-02134-5</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><h4>Abstract</h4>RNA capped with dinucleoside polyphosphates has been discovered in bacteria and eukaryotes only recently. The likely mechanism of this specific capping involves direct incorporation of dinucleoside polyphosphates by RNA polymerase as noncanonical initiating nucleotides. However, how these compounds bind into the active site of RNA polymerase during transcription initiation is unknown. Here, we explored transcription initiation in vitro, using a series of DNA templates in combination with dinucleoside polyphosphates and model RNA polymerase from Thermus thermophilus. We observed that the transcription start site can vary on the basis of the compatibility of the specific template and dinucleoside polyphosphate. Cryo-electron microscopy structures of transcription initiation complexes with dinucleoside polyphosphates revealed that both nucleobase moieties can pair with the DNA template. The first encoded nucleotide pairs in a canonical Watson–Crick manner, whereas the second nucleobase pairs noncanonically in a reverse Watson–Crick manner. Our work provides a structural explanation of how dinucleoside polyphosphates initiate RNA transcription.</div></div>

Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription

In the week of February 9, 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 5 000 GC, LC, MS and spectroscopy webinars.</blockquote><div><div><div><div><div><div><h5>1. Thermo Fisher Scientific: Process Raman – A Reliable and Versatile Tool for Downstream Process Monitoring and Control for mAb Production</h5><ul><li>Tu, 10.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5808">Registration</a></li></ul>The presentation highlights how process Raman spectroscopy offers several advantages over traditional in-line UV-Vis analysis for process monitoring and metabolite production control in mAb manufacturing.<h5>2. Wasson-ECE Instrumentation: The Data Driven Plant – How AI Transforms Chemical Manufacturing</h5><ul><li>Tu, 10.2.2026 21:30 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5744">Registration</a></li></ul>Explore how artificial intelligence is applied to improve process efficiency, monitoring, and decision-making in modern chemical manufacturing.<h5>3. New Food Magazine: The Science of Next-Gen Ingredients – Fermentation, Formulation and Function</h5><ul><li>We, 11.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5720">Registration</a></li></ul>Discover how fermentation-driven innovation is transforming functional food ingredients, with analytical insights to optimize flavour, functionality, and product stability.</div></div></div></div></div></div>

Webinars LabRulezGCMS Week 07/2026

This study presents an analytical strategy combining QuEChERS extraction with low-temperature partitioning (LTP) for the determination of multiclass pesticide residues in cocoa beans by GC–MS. Extraction conditions were optimized using a fractional factorial design, resulting in a simple and efficient workflow suitable for complex cocoa matrices.The validated method showed satisfactory limits of detection and quantification, recoveries within 70–120%, and good overall performance. Application to cocoa samples from Brazil detected permethrin in several samples, demonstrating that the QuEChERS–LTP approach is an effective and reliable cleanup strategy for routine pesticide residue analysis in cocoa.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360">QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans</a></h4>Priscilla M. de Freitas Machado, Madson M. Nascimento, Paulo R. R. Mesquita, Manuela B. Nascimento, Lilian Lefol N. Guarieiro, Gisele O. da Rocha, Jailson B. de Andrade, Raildo M. de Jesus*ACS Omega 2025, 10, 51, 63464–63473<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsomega.5c10360">https://doi.org/10.1021/acsomega.5c10360</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.Cocoa is best known as the primary raw material for chocolate but is also processed into products such as cocoa butter, biscuits, cocoa honey, and cocoa powder. Cocoa powder is derived from roasted, pressed, and milled nibs, containing on average 20% (w/w) lipids on a dry basis and less than 9% moisture. <a href="javascript:void(0);">(3,4)</a>According to the Brazilian Health Regulatory Agency (ANVISA), pesticides such as atrazine, bifenthrin, cyproconazole, metalaxyl, tebuconazole, trifloxystrobin, and permethrin are approved for use in Brazil. <a href="javascript:void(0);">(13)</a> However, among these, only metalaxyl, trifloxystrobin, and tebuconazole are authorized by the European Union. <a href="javascript:void(0);">(14)</a> Thus, investigating these contaminants in cocoa samples is of utmost importance, as Brazil is one of the largest cocoa exporters, supplying cocoa commodities to South America, the United States, and the European Union. <a href="javascript:void(0);">(2)</a> Furthermore, Organochlorine pesticides, in particular, belong to the class of persistent organic pollutants (POPs). Although banned in many countries, they continue to be used in some developing nations because of their chemical stability, resistance to degradation, volatility, and high lipophilicity, which promote bioaccumulation and neurotoxicity. <a href="javascript:void(0);">(15)</a> Epidemiological evidence also associates their exposure with Parkinson’s disease, certain cancers, diabetes, and endometriosis. <a href="javascript:void(0);">(16)</a>Residues of pesticides in cocoa have been reported in various studies. <a href="javascript:void(0);">(17)</a> Analyzing pesticide residues in cocoa presents analytical challenges due to the matrix’s complexity, comprising high lipid content, fatty acids and esters, sugars, polyphenols, and caffeine. These components can interfere with extraction efficiency and contaminate analytical instrumentation. <a href="javascript:void(0);">(18)</a> Therefore, efficient sample preparation methods incorporating effective cleanup steps are essential for accurate residue determination.Several techniques have been employed for multiresidue pesticide analysis in cocoa. For instance, Idowu et al. <a href="javascript:void(0);">(19)</a> quantified 14 organochlorines using Soxhlet extraction and silica/Na2SO4 cleanup, with GC ECD detection. Okoffo et al. <a href="javascript:void(0);">(20)</a> determined 13 organophosphates and 9 pyrethroids employing SPE cartridges (Envi-carb/LC-NH2 and Bond Elute C18), acetonitrile extraction, and GC PFPD or GC ECD quantification. Yusiasih et al. <a href="javascript:void(0);">(21)</a> applied dispersive SPE with PSA, Florisil, and MgSO4 for pyrethroids, followed by GC ECD and GC–MS.Therefore, this study aimed to evaluate the effectiveness of a QuEChERS–LTP analytical procedure for the determination of multiclass pesticide residues in cocoa beans. The factors that affect the QuEChERS–LTP procedure efficiency were optimized. After validation, the procedure was employed to investigate the occurrence of 15 multiclass pesticides in cocoa samples.<h4>Experimental Section</h4><h5>Instrumental Apparatus</h5>Pesticide separation and identification were performed on a Shimadzu <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GC-MS-QP2010SE">GC-MS-QP2010SE</a> system (Kyoto, Japan) equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-20i">AOC-20i autosampler</a>. Separation was achieved using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-5MS">Agilent DB-5MS capillary column</a> (30 m × 0.25 mm × 0.25 μm) with a stationary phase of 5% phenyl/95% dimethylpolysiloxane. The instrumental conditions were based on Nascimento et al. <a href="javascript:void(0);">(49)</a> and they are summarized in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl4">Table 4</a>.For quantification, the base peak was used, while two additional ions were monitored for confirmation (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Table S2</a>) in accordance with SANTE guidelines. <a href="javascript:void(0);">(50)</a> A GC–MS/SIM chromatogram illustrating the separation of all target pesticides is presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig5">Figure 5</a>.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 5. Extracted ion chromatogram (EIC) in SIM mode of the target pesticides obtained from the injection of a mixed standard solution at 100 μg L–1. Analytes are listed in order of elution: [1] Molinate (6.18 min); [2] α-HCH (8.15 min); [3] atrazine-d5 (8.69 min); [4] atrazine (8.75 min); [5] diazinon (9.31 min); [6] disulfoton (9.67 min); [7] dimethachlor (10.60 min); [8] metalaxyl (11.25 min); [9] p,p′-DDE (15.82 min); [10] cyproconazole I (16.50 min); [11] cyproconazole II (16.56 min); [12] p,p′-DDD (17.29 min); [13] ethion (17.34 min); [14] trifloxystrobin (18.43 min); [15] tebuconazole (19.13 min); [16] bifenthrin (20.47 min); [17] permethrin I (23.92 min); [18] permethrin II (24.18 min)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg 245w," sizes="100vw" width="2080" height="835"><h5>Application of the Proposed Procedure to Real Samples</h5>In a 50 mL Falcon tube, 2.0 g of sample was weighed using an analytical balance (AUX320, Shimadzu, Kyoto, Japan). A total of 2.0 g of salt (NaCl and Na2SO4 in a 1:1 w/w ratio) was added, followed by an aliquot of the atrazine-d5 solution (surrogate standard) to yield a final concentration of 250 μg kg–1. A mixture of acetonitrile (8.0 mL) and ultrapure water (2.0 mL) was then added. The system was vortexed (K40-10208, Kasvi, São Paulo, Brazil) for 3.0 min at 2500 rpm and centrifuged (MPW-351R, MPW Med. Instruments, Warsaw, Poland) for 10.0 min at 15 °C and 10,000 rpm. After phase separation, approximately 6.0 mL of the supernatant was transferred to a Falcon tube containing 150.0 mg of PSA sorbent. The mixture was vortexed again for 3.0 min at 2500 rpm and centrifuged for an additional 10.0 min under the same conditions. The tubes were then placed in the freezer for 24 h. Once the aqueous phase had frozen, the organic extract containing the analytes was collected, filtered through a Cytiva Whatman MiniUniprep G2 vial with a 0.20 μm membrane filter (Marlborough, Massachusetts, USA), and injected into the GC–MS system (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig6">Figure 6</a>).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 6. Schematic representation of the extraction procedure using the QuEChERS–LTP procedure for pesticide extraction in cocoa powder samples." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg 223w," sizes="100vw" width="1458" height="1022"><h4>Results and Discussion</h4><h5>Evaluation of the Effect of Low and Ultralow Temperatures on the Analytical Response</h5>Studies reporting the use of LTP generally employ a conventional freezer, which typically reaches −18 ± 2 °C as the minimum temperature. In this equipment, effective phase separation can require 8 to 24 h. <a href="javascript:void(0);">(35−37)</a> In contrast, ultralow temperature freezers (ultrafreezers) can reach −80 °C, leading to a substantial reduction in partitioning time. In this study, tests performed with the conventional freezer achieved satisfactory partitioning after 24 h, whereas in the ultrafreezer, complete partitioning was observed in only 20 min.Considering the analytical response in terms of peak area (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>), higher signals were obtained when LTP was performed in a conventional freezer rather than an ultrafreezer. This behavior can be attributed to the partitioning mechanism. <a href="javascript:void(0);">(32)</a> Partitioning depends on cooling and the subsequent freezing of the aqueous phase. In the conventional freezer, the slower freezing rate provides sufficient time for the system to approach thermodynamic equilibrium, favoring analyte diffusion between phases. Under these conditions, analyte molecules have more time to migrate and distribute optimally before complete solidification. In contrast, the rapid freezing in the ultrafreezer may trap analytes in a nonideal distribution, reducing the efficiency of the partitioning process <a href="javascript:void(0);">(32)</a> (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>). According to these observations, the conventional freezer was selected for subsequent experiments.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 3. Comparison of chromatographic peak areas of pesticides after partitioning in the conventional freezer versus the ultrafreezer." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg 175w," sizes="100vw" width="996" height="891"><h5>Application to Real Samples</h5>Fifteen samples were analyzed in triplicate, comprising two from the State of Pará and 12 from the State of Bahia, located in the North and Northeast regions of Brazil, respectively. Among the 15 pesticides investigated, only permethrin isomers were quantified in four samples (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a>). The herbicide molinate was also detected in three samples; however, its concentration was below LOQ. Permethrin isomers concentrations ranged from 17.1 ± 0.3 to 49.6 ± 1.8 μg kg–1. These values are below the MRL established by European Union regulation, which is 100 μg kg–1. <a href="javascript:void(0);">(42)</a> Although permethrin is not permitted in the European Union, <a href="javascript:void(0);">(42)</a> it remains authorized for use as insecticide in Brazil, particularly in crops such as cotton, rice, coffee, citrus, cabbage, beans, tobacco, maize, soybean, tomato, wheat, and grape. <a href="javascript:void(0);">(13)</a> However, no MRL values have been established for cocoa beans under Brazilian legislation. <a href="javascript:void(0);">(13)</a> <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a> shows the concentration of detected compounds in the cocoa samples.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Table 3. Mean Concentrations (μg kg–1 ± Standard Deviation) of Target Pesticides Detected in This Study" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg 196w," sizes="100vw" width="1070" height="851">To assess method performance for pesticides not detected in the cocoa samples, one of the analyzed samples was fortified with a mixed standard solution at concentrations of 50, 250, and 500 μg kg–1. The fortified analytes were subsequently detected in the chromatograms presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Figures S2–S4</a>, indicating good response of the proposed method.<h4>Conclusions</h4>The QuEChERS–LTP procedure was successfully developed for the determination of 16 multiclass pesticide residues in cocoa beans. For the first time, ultralow temperature (−80 °C) was applied to accelerate the low-temperature partitioning process during pesticide extraction from cocoa beans. Nevertheless, conventional freezing at −12 °C proved to be more effective for the extraction of the target analytes.Evaluation of the matrix effect demonstrated that matrix-matched analytical curves, constructed in an analyte-free cocoa bean extract, were more effective in compensating for matrix interferences than the use of analyte protectants.The pyrethroid permethrin was quantified in four cocoa samples. However, the concentrations did not exceed the MRL established by European Union legislation.Overall, the QuEChERS–LTP procedure proved to be a promising approach for pesticide residue determination, as it requires smaller volumes of solvents and reagents, involves fewer cleanup and extraction steps, and shows strong potential for application to other complex matrices.

QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans

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The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) is a leading scientific institution in the Czech Republic, recognized internationally. Its primary mission is basic research in the fields of chemical biology and medicinal chemistry, organic and material oriented chemistry, chemistry of natural compounds, biochemistry and molecular biology, physical chemistry, theoretical chemistry, and analytical chemistry. 

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences

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Thinking of developing a new method utilizing MS? Selecting the best analytical method begins with a decision on how to best separate the analytes of interest. This choice will affect sample preparation and sample introduction, so it is important to get it right early. In this webinar we will review analyte structural properties that make the compound more amenable to either liquid chromatography or to gas chromatography.
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Presenter: Karen Yannell (LC/MS Application Engineer, Agilent Technologies, Inc.)
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Karen E. Yannell is a LC/MS Application Engineer at Agilent Technologies. She is an expert in small molecule high throughput analysis by triple quadrupole (TQ) and quadrupole time-of-flight (QTOF) mass spectrometry for applied markets. Her recent work has focused on developing routine Q-TOF workflows for both expert and non-expert users alike. Previously, Karen worked on forensic, metabolomics, and biomarker discovery applications with ambient ionization sources. She received her PhD in Analytical Chemistry from Purdue University where studied under the advisement of Prof. R. Graham Cooks. Outside of the laboratory, she enjoys cooking unique dishes and hiking along the beach with her dog.
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Presenter: David Weil, PhD (Senior Applications Scientist, Agilent Technologies, Inc.)
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David Weil is a senior applications scientist in Agilent located in Wood Dale with over 30 years of experience using mass spectrometry. Prior to joining Agilent in 2004, he worked for 14 years at 3M in the Corporate Research Analytical Laboratories (St.Paul, MN) and 4 years at Nicolet/Extrel doing ultra-high resolution mass spectrometry. David received his Ph.D. in Physical Chemistry from the University of Minnesota and Post Doc with Dr Charles Wilkins at University of California-Riverside developing laser desorption FTMS and ion-molecule reactions. David has three grown sons and live with his wife Naomi just blocks from Wrigley Field and Lake Michigan.
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</blockquote>

Agilent Technologies: Selecting your Separation: Are my Compounds Better for GC or LC

Selecting your Separation: Are my Compounds Better for GC or LC

We will review analyte structural properties that make the compound more amenable to either liquid chromatography or to gas chromatography.

Separation selection: Are my Compounds Better for GC or LC

We probably have all experienced this at some point when performing gas chromatography—our peak shape begins to appear a bit different.
In this webinar, we will discuss some of the most common chromatographic issues that you experience with gas chromatography and take a logical approach to finding the root cause and correcting the problem. Often the best way to approach troubleshooting is to also consider what cannot cause an issue so that precious time is not spent addressing something that is not relevant to the symptoms.
This webinar will arm you with simple tools, and a different way to look at troubleshooting, should a problem arise.
<blockquote>
Presenter: Alex Ucci (Application Engineer, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
In his current position at Agilent, Alex provides application assistance and technical support for sample preparation products as well as GC and LC consumables. Before he joined Agilent in 2014, Alex was a graduate student at the Pennsylvania State University researching the morphology and surface properties of aerosol particles using a wide variety of analytical techniques. He has an MS degree in chemistry.
</blockquote>

Agilent Technologies: Take the Trouble Out of Troubleshooting: Gas Chromatography

Take the Trouble Out of Troubleshooting: Gas Chromatography

The most common chromatographic issues that you experience with GC and take a logical approach to finding the root cause and correcting the problem.

Are you feeling the impact of Helium Shortage 4.0? We understand the difficulties and concerns you may be facing. From delays to longer turnaround time and rising costs, the GC analysis has indeed taken a direct hit from the fluctuating global helium levels.
To help users combat the issue, Shimadzu offers flexible solutions to ensure smooth operation while saving costs for GC analysis. In this webinar, learn how our GC instruments can effectively reduce helium consumption or switch easily to a different carrier gas for uninterrupted analysis. With Shimadzu, you can confidently navigate through the uncertain times brought on by Helium Shortage 4.0.
Join us and let&#39;s overcome this challenge together.
<h5>Learning Objectives:</h5>
<ul>
<li>How Shimadzu offers countermeasures to address the urgent issue of Helium Gas Supply Shortages</li>
<li>Learn about the capabilities of Shimadzu&#39;s GC instruments in reducing helium consumption for lower cost of analysis</li>
<li>Learn about the flexibility of Shimadzu&#39;s GC instruments to switch carrier gas easily to ensure uninterrupted analysis</li>
</ul>
<blockquote>
Presenter: Ryo Takechi (Global GC Product Manager, Shimadzu Corporation)
</blockquote>
<blockquote>
Ryo has a background in gas chromatography and engineering of analytical instrumentation over 10 years. He earned degrees in chemical engineering from Doshisha University in Kyoto, Japan.
</blockquote>
<blockquote>
Q&amp;A Respondent: Dr. Jackie (Assistant Product Manager (GC &amp; GCMS), Shimadzu (Asia Pacific) Pte Ltd)
</blockquote>
<blockquote>
Dr. Jackie obtained his PhD in Analytical Chemistry from the National University of Singapore. He has garnered over 9 years of research, training, and facilitation experience. Jackie meets scientists from various industries to share technical knowledge and collect feedback, understanding their problems and helping them find well-suited solutions in GC-related analyses.
</blockquote>

Shimadzu: Beat the Helium Shortage, Time to Think Hydrogen!

Beat the Helium Shortage, Time to Think Hydrogen!

Learn how our GC instruments can effectively reduce helium consumption or switch easily to a different carrier gas for uninterrupted analysis.

The presentation will introduce DiscovIR-GC® (FTIR) as a universal detector that can be coupled with any Gas Chromatograph, using solid-phase direct deposition to afford unique molecule fingerprinting, while boosting the resolution and sensitivity over conventional gas phase devices.
FTIR is a powerful tool for the identification of specific isomers of controlled substances and when integrated with MS, accuracy of identification is superior. By joining the strengths of the FTIR and MS detectors, the characterization of unknowns is easily performed in a single analysis. FTIR allows for spectral distinction between positional isomers where identification by MS is limited.
As a walk-up instrument, the DiscovIR-GC system is designed to meet the needs of forensic drug chemistry laboratories and make use of spectral databases for rapid and accurate identification of unknowns through the orthogonal information gathered from FTIR.
Learning Objectives of Webinar:
<ul>
<li>Understand the technology behind solid-phase deposition FTIR coupled with GC</li>
<li>Gain insight into the differences between gas phase IR and solid-phase IR spectroscopy</li>
<li>Understand the capability for identification of synthetic opioids based on structural differences in IR finger printing</li>
</ul>
<blockquote>
Presenter: Nathan Hawkins (CEO, Spectrometrics Limited)
</blockquote>
<blockquote>
Nathan is the CEO of Spectrometrics, UK. He managed a metabolomics core facility for 14 years, before moving into a hybrid commercial role that included account and product management of a small instrument vendor’s portfolio of life science &amp; forensics instruments.
</blockquote>
<blockquote>
He established Spectrometrics in 2022 to bring new &amp; emerging analytical technologies to the UK &amp; Ireland.
</blockquote>
<blockquote>
Presenter: Tracy Phillpott (Senior Applications Chemist,, Spectra Analysis Instruments, Inc.)
</blockquote>
<blockquote>
Tracy Phillpott is the Senior Applications Chemist with Spectra Analysis Instruments, USA. She has a Bachelor’s in Textile Chemistry from Auburn University. Her previous experience has been in the Textile, Polymer, Tire, and Pharma Industries for Morton International, Michelin Americas R&amp;D, Schweizerhall Development Company and IRIX Pharmaceuticals.
</blockquote>

The Analytical Scientist: DiscovIR-GC® Detector: Integration of GC-FTIR and MS as a Unique Tool in the Identification of Positional and Structural Isomers

DiscovIR-GC Detector: Integration of GC-FTIR and MS as a Unique Tool in the Identification of Positional and Structural Isomers

The presentation will introduce DiscovIR-GC (FTIR) as a universal detector that can be coupled with any Gas Chromatograph.

DiscovIR-GC Detector: Integration of GC-FTIR and MS

This webinar will cover the analysis of pesticides in food and highlight the productivity enhancement features available on Thermo Scientific chromatography systems.
We will look at the analysis of pesticides using GC-MS/MS with helium conservation and the use of alternative carrier gas to ensure sustainable productivity. 
Our experts will show how single software platform can optimize your pesticides analysis and drive efficiency in your laboratory for GC-, LC-, IC-, MS/MS analysis.
Dual sequence processing, where data can be merged to provide orthogonal cross confirmation of identity and increased confidence in results will be discussed.
It will also be demonstrated how the software supports SANTE analytical quality control criteria for compliant analysis.
<blockquote>
Presenter: Łukasz Rajski (Product Specialist, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Łukasz Rajski works as product application specialist at Thermo Fisher Scientific. He holds a Ph.D. in analytical chemistry. Łukasz has over 10 years of experience in pesticide residue analysis. He is an expert in the development and validation of analytical methods. Dr. Rajski works with advanced mass spectrometry techniques (both high-resolution and triple quadrupole) coupled to ultra-high performance liquid chromatography, high-performance ion chromatography, and gas chromatography. Łukasz Rajski is a co-author of numerous articles published in scientific journals with high impact factor and book chapters dedicated to pesticide residue analysis
</blockquote>
<blockquote>
Presenter: Zoe Julian (Product Marketing Manager, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Zoe Julian is a product marketing manager for chromatography software within the CMD Software team at Thermo Fisher Scientific. With over 12 years&#39; experience of working with chromatography and mass spectrometry techniques with a background in GC and GC-MS(/MS) organic environmental analysis, she has helped many laboratories and industries improve their workflows through a unique understanding of their challenges. Transitioning to a focus on Thermo Scientific™ Chromeleon™ CDS, she has shown customers how software solutions can improve their productivity and support their day-to-day operations.
</blockquote>

Pixabay/DanaTentis: Sustainable productive pesticide analysis

Sustainable productive pesticide analysis

This webinar will cover the analysis of pesticides in food and highlight the productivity enhancement features available on chromatography systems.

Webinars will cover the following Gas Chromatography topics:
<ul>
<li>6/27 - Vaporizers for LPG Samples</li>
<li>7/11 - Dynamic Blending for Linearity and LDL</li>
<li>7/18 - GC Valves: Purposes and Service</li>
<li>7/25 - Calibration Techniques for Accurate Data</li>
<li>8/1 - Sample Capture, Transport, and Introduction</li>
<li>8/8 - GC Detectors I: PDHID and SCD</li>
<li>8/15 - GC Autosamplers for Gas and LPG Samples</li>
<li>8/22 - GC Detectors II: The Strengths of Mass Spectrometry</li>
<li>8/29 - Methanizers for Trace CO &amp; CO2</li>
<li>9/5 - Training Program for GC Operators</li>
</ul>
<blockquote>
Presenter: John Wasson (President, Wasson-ECE Instrumentation, Inc.)
</blockquote>
<blockquote>
John Wasson has over 40 years of experience in Gas Chromatography and Chemical Instrumentation.
</blockquote>

Wasson-ECE Instrumentation: Free GC Webinar Series

Vaporizers for LPG Samples

Dynamic Blending for Linearity and LDL

Following up from our very successful previous sessions, we are delighted to offer another panel discussion in the ever popular “Ask the Agilent Experts” series.
Have you ever had a question about your GC/GCMS analysis and thought, “I have no idea what to do,” or that since the question seemed so simple, everyone must already know the answer and &quot;Am I the only one who doesn’t know what to do?” We can assure you that you are not alone.
If you have a question, we can guarantee that you are not the first...nor the last person to ask the question. Sometimes the simplest of questions can have the most complex answers. A question about which liner to use can lead to a discussion on the benefits of glass wool versus glass frits. A question about how long a column should last may trigger a discussion about the importance of a leak free system, the maximum temperature limit, proper phase selection, and how an application may benefit from using backflush. There’s no such thing as an easy answer because the answer always “depends” on many different factors. 
We will discuss some of the most frequently asked questions about GC and GCMS that we have received. Some may seem like simple questions, but they have anything but simple answers. Experts from Agilent as well as from the field will also answer new questions that we hope you will submit to us in advance.
<blockquote>
Presenter: Vanessa Abercrombie (MFS, GC Applications Chemist, Agilent Technologies)
</blockquote>
<blockquote>
Vanessa has a broad background in GC and GC/MS, including experience as an instrument chemist at Bode Technology in Virginia working under contract to the FBI’s Laboratory Division. Prior to that, Vanessa worked for ETS Labs in St. Helena, California as an Analytical Chemist where she researched and developed quantitative separations by GC/MS and UHPLC for beer, wine and spirits. She holds a Masters of Forensic Science from The George Washington University and a Bachelor of Arts in Chemistry from Sonoma State University.
</blockquote>
<blockquote>
Presenter: Samuel Haddad (Ph.D., Application Development Chemist, Agilent Technologies)
</blockquote>
<blockquote>
Samuel Haddad is a GC Application Development Chemist at Agilent Technologies in Wilmington, Delaware. Samuel specializes in GC and GCMS applications of trace analysis in environmental and heavy matrix samples. His specialty includes sample preparation techniques to separate analytes from matrix components and extraction from a wide variety of matrix including water, fish, aquatic life, soil, and complex fluids. Samuel holds a Ph.D. in Environmental Science from Baylor University and a B.S in Biology from Southern Illinois University Edwardsville.
</blockquote>
<blockquote>
Moderator: Diane Turner (Director &amp; Senior Consultant, Anthias Consulting Ltd)
</blockquote>
<blockquote>
A Warwick University graduate, Diane completed her masters in Analytical Chemistry and started her career in environmental chemistry, later gaining significant experience as an Applications Chemist. Diane’s area of research through her PhD studies at The Open University was disease diagnosis. She has developed methods and given support and training for companies in most industries around the world for more than 20 years. Diane holds voluntary roles with The Royal Society of Chemistry and other scientific organizations.
</blockquote>

Separation science: Ask the Agilent Experts - Part 4: GC and GC/MS Scientists Discuss & Answer Your Most Frequently Asked Questions

Ask the Agilent Experts - Part 4: GC and GC/MS Scientists Discuss & Answer Your Most Frequently Asked Questions

The most frequently asked questions about GC and GCMS that we have received.

Ask the Agilent Experts - Part 4: GC and GC/MS

Welcome to Thermo Fisher Scientific’s Powering Productivity in Food and Environmental Testing webinar series!
The global helium shortage continues to have a profound impact on the productivity of analytical testing labs that rely on helium as a carrier gas for their GC analyses.
In this webinar, hosted by Petra Gerhards, GC&amp;GC-MS experts Daniela Cavagnino and Adam Ladak will discuss the recurring shortage, the effect it is having on gas chromatography users, and solutions that Thermo Fisher Scientific can provide to help reduce the burden of increased cost and supply uncertainty in routine testing labs. The solutions covered include technologies for saving helium, as well as using hydrogen instead of helium- including data that validates the workflow for hydrogen usage.
<blockquote>
Presenter: Daniela Cavagnino (Product Marketing Manager, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Dr. Daniela Cavagnino received a Master Degree in Chemistry at the University of Milan, Italy. She started her career in gas chromatography at Thermo Fisher Scientific spending several years in the R&amp;D laboratories working on GC technology innovation and more than 15 years in product and marketing management roles promoting GC/GCMS technology and applications.
</blockquote>
<blockquote>
Presenter: Adam Ladak (Global Product Marketing Manager, GC Quadrupole MS, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Adam started his career working in a contracting testing lab analyzing sports supplements and horse feed for prohibited substances. Adam spent over 10 years working for a leading instrument manufacturer in various roles from an application specialist in the UK and the US to a global marketing role focus on food and environmental testing. Adam is passionate about utilizing our GC-MS instrumentation to meet customer needs and solve real-world problems.
</blockquote>

Thermo Scientific: Ask-the-experts on effective GC solutions to deal with the helium shortage

Ask-the-experts on effective GC solutions to deal with the helium shortage

Technologies for saving helium, as well as using hydrogen instead of helium- including data that validates the workflow for hydrogen usage.

Effective GC solutions to deal with the helium shortage

Does the supply or cost of Helium carrier gas concern you &amp; the profitability of your lab?
Are you looking to switch to a faster &amp; cost-effective alternative?
Learn more by joining us for the upcoming webinar, where we will discuss the possibilities to save on helium costs &amp; to switch away from helium as a carrier gas.
The webinar will focus on the advantages and disadvantages of switching to a different carrier gas, as well as the implications of the same. 
We will talk about an innovative addition to the Agilent portfolio that offers opportunities to equip GC-MS systems in such a way that working with hydrogen as a carrier gas will lead to better results than was ever possible before. 
Key learning objectives: 
<ul>
<li>What are the options to save on Helium carrier gas cost
</li>
<li>Learning the implications of moving away from Helium as a carrier gas
</li>
<li>Implementing alternatives for Helium carrier gas
</li>
</ul>
Who should attend: Everyone using Helium as a carrier gas for GC/GC-MS application and those who want to save on Helium costs or are forced to move away from Helium for varied reasons. 
<blockquote>
Presenter: Dr. Anshu Kumari Singh (Technical Support Manager, Agilent Technologies)
</blockquote>
<blockquote>
Dr. Anshu Kumari Singh is the Technical Support Manager for India in the Chemistries and Supplies Division. She has more than 20 years of experience in this industry. She is leading a team of highly qualified Individuals responsible for providing technical support to customers. She provides support to customers on queries related to applications, products and troubleshooting for GC and LC columns and Supplies. She also conducts workshops, trainings and seminars for the customers helping them in understanding the chemistry behind GC &amp; HPLC columns and Sample Preparation Products. Dr. Anshu holds a Doctorate degree from Indian Agricultural Research Institute, New Delhi and is based out of Delhi.
</blockquote>
<blockquote>
Presenter: Praveen Arya (Application Engineer - GCMS, Agilent Technologies
</blockquote>
Praveen Arya, Application Engineer at Agilent technologies, has a commitment and appreciation for Gas-phase residue applications. In 2005, Mr. Praveen Arya completed his MSc. in Food Technology . After post-graduation, he served as a Senior Analyst at SGS, Gurgaon- a commercial testing laboratory for 6 years and developed expertise in Residue analysis using sophisticated chromatographic instruments such as LCMS and GCMS. After that, in 2011, He joined Agilent Technologies as an Application Engineer where he supported country-wide GCMS customers for resolving application issues and method development. He has more than 18 years of experience in residue analysis in food and environmental samples using various high end chromatographic and spectrometric techniques (GC, GCMS, GCMS/MS, TDS, Headspace, Purge &amp; trap etc.). His area of specialization includes new analytical method development and validation as per national and international guidelines.

Agilent Technologies: The Helium to Hydrogen Switch

The Helium to Hydrogen Switch

We will discuss the possibilities to save on helium costs & to switch away from helium as a carrier gas.

GCMS webinars focusing on GC - page 14