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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Injecting water into your GC may be convenient, especially if you are working with compounds that have limited solubility in organic solvents or with water samples. However, there are many potential problems with water, including injector and detector issues.
Join us as we take a dive deep and explore water injections and not only how to perform them correctly, but also the many pointers to keep in mind when working with water.
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Presenter: Mark Sinnott (Application Engineer, Agilent Technologies, Inc.)
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Mark Sinnott works for Agilent Technologies as a Technical Support Engineer in the Consumables and Supplies Division (CSD). In his position at Agilent, Mark performs technical support and applications assistance to gas chromatographers worldwide. He has more than 22 years of experience in gas chromatography, including environmental analysis of compounds in air, soil and water matrices, including dissolved gas analysis for the electrical industry. Mark holds a Master’s Degree in Chemistry from California State University, Sacramento, and currently resides in Twin Falls Idaho.
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Agilent Technologies: Navigating Troubled Waters: A Deep Dive into Water Injections by GC

Navigating Troubled Waters: A Deep Dive into Water Injections by GC

Water injections and not only how to perform them correctly, but also the many pointers to keep in mind when working with water in GC.

A Deep Dive into Water Injections by GC

In today’s ever-changing laboratory environment, sample throughput and security of supply are paramount in maintaining productivity. With the recent limited availability and cost increase of helium, many labs are looking at ways to conserve and convert.
In this webinar, we will demonstrate how simple column and consumables choices can improve speed of analysis, while also minimizing the use of carrier gas. We will also illustrate how these same consumables will provide the flexibility needed to simplify conversion to hydrogen carrier gas, if needed. Finally, we will provide some simple, under-utilized tips on how to conserve your current gas use.
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Presenter: Ashlee Gerardi (Product Marketing, Agilent Technologies, Inc.)
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Agilent Technologies: How to Go Fast and Make Your Carrier Gas Last

How to Go Fast and Make Your Carrier Gas Last

How simple column and consumables choices can improve speed of analysis, while also minimizing the use of carrier gas.

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 the leaks on your mass spectrometer can lead to a discussion about selecting the proper filaments. A question about troubleshooting a bad injection can lead to a conversation about syringes, plungers, and even vial septa. There’s no such thing as an easy answer because the answer always &#39;depends&#39; on many different factors. 
We will discuss some of the most frequently asked questions about GC and GCMS that we have received, which may seem like simple questions, but they have anything but simple answers as well as new questions that we hope you will submit to us in advance with experts from Agilent as well as from the field.
By attending this presentation you will learn about:
<ul>
<li>Best practices with GC and GC/MS systems – from troubleshooting injections to how leaks can affect your mass spectrometer and why there is not always an easy answer to most GC(MS) questions
</li>
<li>Why different consumables are used for different applications - listen to Agilent scientists discuss the complexities of the most frequently asked questions they receive
</li>
<li>What backflush is and how to set it up
</li>
</ul>
<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>
Presenter: 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>

LabRulez/AI: Ask the Agilent Experts - Part 5: GC and GC/MS Scientists Discuss & Answer Your Most Frequently Questions

Ask the Agilent Experts - Part 5: GC and GC/MS Scientists Discuss & Answer Your Most Frequently Questions

Best practices with GC and GC/MS systems. Why different consumables are used for different applications. What backflush is and how to set it up...

GC and GC/MS Scientists Discuss & Answer Your Questions

In the world of GC, helium is the long standing “go to” carrier gas for most GC applications, but the variable price and uncertain supply over recent years is driving laboratories to consider alternatives such as hydrogen.
But when transitioning to hydrogen carrier gas what is the impact on method performance and what about the safety concerns? In this webinar, our GC&amp;GC-MS experts Daniela Cavagnino and Adam Ladak will answer these questions, including how your helium consumption can be significantly reduced if moving to hydrogen is just not an option. This webinar is your opportunity to get real world solutions to this challenge and to learn more.
We want to hear from you - Please send us your questions in advance during registration or anytime via email to analyze.eu@thermofisher.com. This will allow the team to group incoming questions under common topics. 
You will also be able to submit questions during the live session, through the Q&amp;A chat function. If we don’t get to your question during the webinar, we will reach out to you afterwards. We look forward to some great engagement and to enable you to be fully up to speed with regards carrier gas alternatives.
<blockquote>
Presenter: Daniela Cavagnino (Product Marketing Manager GC&amp;GC-MS, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Presenter: Adam Ladak (Global Product Marketing Manager GC Quadrupole Mass Spectrometry, Thermo Fisher Scientific)
</blockquote>

Thermo Scientific: Is it time to consider an alternative GC carrier gas?

Is it time to consider an alternative GC carrier gas?

How your helium consumption can be significantly reduced if moving to hydrogen is just not an option.

Learn how to intelligently manage your risk by signing up for “How to Buy a GC”.
Presenter: John Wasson (Presindent)

How to Buy a GC

Learn how to intelligently manage your risk by signing up for “How to Buy a GC”.

Minimize risk, streamline workflows and improve the reliability of your analytical measurements.
How do the Alliance iS and Empower work together to reduce common human errors?
Empower 3.8.0 offers unique features that work specifically with Waters Alliance iS HPLC System and can reduce common made human errors.
Learn how to identify potential errors earlier, reduce the number of retests and failure investigations and register!
<blockquote>
Presenter: Arjan Timmerman (Principal Pharma Market Development Manager Pharmaceuticals, Compliance and Impurities)
</blockquote>
<blockquote>
Presenter: Andrea Gheduzzi (Principal LC Market Development Manager, EMEA)
</blockquote>
<blockquote>
Presenter: Carsten Fischer (Informatics Product Marketing, EMEA)
</blockquote>

Waters Corporation: Reducing Human Errors with Empower 3.8.0

Reducing Human Errors with Empower 3.8.0

Empower 3.8.0 offers unique features that work specifically with Waters Alliance iS HPLC System and can reduce common made human errors.

We just faced a new Helium shortage period which resulted in important price increase but also in supply issue.
These critical events are becoming more and more frequent and if today there is no more issue with Helium delivery the price is still extremely high and will continue to increase. 
In order to secure the lab from potential future shortage but also to reduce the analysis cost more and more analyst are switching to alternate carrier gas.
<blockquote>
Presenter: Laurent Pascaud (Product Specialist GC &amp; GC/MS, Agilent)
</blockquote>
<blockquote>
After 10 years of experience within the French Anti-Doping Agency, Laurent Pascaud joined Agilent Technologies in 2007.
</blockquote>
<blockquote>
He now has over 15 years of analytical development expertise, first as an applications engineer and then as a GC and GCMS product specialist in various chemical markets.
</blockquote>

Agilent - Tips & Tricks for a Smooth Transition from Helium to Alternate Carrier Gas

Tips & Tricks for a Smooth Transition from Helium to Alternate Carrier Gas

In order to secure the lab from potential future shortage but also to reduce the analysis cost more and more analyst are switching to alternate carrier gas.

Smooth Transition from Helium to Alternate Carrier Gas

In Gas chromatography 90% of trouble occurs in the injection system.
In this troubleshooting session we will discuss the 10 most important maintenance points focusing on split/splitless injection systems. We will discuss the purpose and impact of the critical parts and setup used in split and splitless injection and how it impacts your results. We will then cover installation, peak shape, contamination sources for sample and system, carrier gas, maintenance and life time using practical examples.

Restek Corporation: Top 10 Maintenance Tips For Your GC Split/Splitless Injection System

Top 10 Maintenance Tips For Your GC Split/Splitless Injection System

In this troubleshooting session we will discuss the 10 most important maintenance points focusing on split/splitless injection systems.

Maintenance Tips For GC Split/Splitless Injection System

Are you using Chromeleon Chromatography Data System (CDS) but don’t feel like an expert just yet? Are you interested in a CDS that is intuitive and user-friendly? Whether you’re a day-to-day user or just exploring new possibilities in the world of CDS, this webinar is tailored for you!
Join us and discover how the Chromeleon CDS can elevate your experience and make the tasks simpler.
<h5>What this session covers:</h5>
<ul>
<li>Fundamentals of Chromeleon CDS</li>
<li>Creation of custom reports</li>
<li>New features in Chromeleon 7.3.2 CDS</li>
<li>Benefits of upgrading from workstation to enterprise with the Ardia Platform</li>
</ul>
<blockquote>
Presenter: Seth Sheridan (Product Specialist III, Enterprise CDS, Americas, Thermo Fisher Scientific)
</blockquote>
<blockquote>
Seth is an Enterprise CDS technical specialist who has supported Thermo Fisher Scientific’s Chromeleon software for over 3 years. Prior to this, he used Chromeleon and other CDS systems in labs at DuPont, DOW, and Eurofins. He holds a B.S. in Chemistry and Biochemistry and enjoys working closely with chromatographers to solve their software issues and improve their processes.
</blockquote>

Chromatography & Mass Spectrometry: Back to Basics – Tips and Tricks of Chromeleon CDS

Back to Basics – Tips and Tricks of Chromeleon CDS

Join us and discover how the Chromeleon CDS can elevate your experience and make the tasks simpler.

<h3>PhenoAcademy Webinars - Gas Chromatography Series</h3>
<h4>Troubleshooting for Gas Chromatography</h4>
<ul>
<li>Master how to recognize symptoms of challenges with method performance</li>
<li>Identify active sites and impurities within the column and system</li>
<li>Understand how to attribute common maintenance practices to specific remedies</li>
</ul>
<blockquote>
Presenter: Duilio Romanello (Senior Technical Specialist, Phenomenex)
</blockquote>
<blockquote>
Duilio Romanello graduated with his Bachelors of Science in Pharmaceutical Chemistry and Technology from University of Bologna. Duilio then joined Phenomenex in 2008 as an Inside Technical Sales Consultant becoming Team Leader in Italy for GC/SPE in 2010 and then for the Environmental &amp; Food Team.
</blockquote>
<blockquote>
Since 2016 he has been covering the role of Account Manager for the South of Italy working remotely and acting as GC Specialist. Since November 2023 he is Senior Technical Specialist for the Technical team at Phenomenex.
</blockquote>
<blockquote>
Presenter: Zachary Woodward (Senior Technical Specialist, Phenomenex)
</blockquote>
<blockquote>
Zachary Woodward is a Senior Technical Specialist with Phenomenex, Inc, assisting laboratories with method development in the bio-pharma, environmental, and food industries. Zachary spent his formative years developing HPLC and GC methods with a pharmaceutical lab in Albany, NY, after which he developed HPLC and SPE methods in the clinical setting here in Southern California. Zachary received his B.Sci. in Chemistry from the College of William and Mary, was awarded his Master’s in Chemistry at San Diego State University, and is happy to speak with you today!
</blockquote>
<blockquote>
Presenter: Lucia Geis Asteggiante (Senior Technical Specialist, Phenomenex)
</blockquote>
<blockquote>
Lucia is a Senior Technical Specialist that has recently joined Phenomenex’s Global Technical Team. She has a broad experience in the field of Analytical Chemistry with a particular focus on LC chromatography coupled with mass spectrometry. Lucia comes from a strong academic and regulatory background with experiences ranging from method development and analysis of small molecules to large protein complexes. She gained her Ph.D. at the University of Maryland - College Park, USA and did her post-doctoral work at the University of Oxford, UK. During her time as a researcher, she has authored/co-authored 23 scientific publications and 2 book chapters.
</blockquote>

Troubleshooting for Gas Chromatography

Recognize symptoms of challenges with method performance , identify active sites and impurities within the column and system

GCMS webinars focusing on Tips & Tricks - page 8