<p><strong>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 </strong><i><strong>Nature Chemical Biology</strong></i><strong>.</strong></p><p><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"></p><div><p>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.</p><p>In their study,<strong> </strong><a target="_blank" rel="noopener noreferrer" href="https://cahova.group.uochb.cz/en"><strong>Dr. Hana Cahová</strong></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.</p><p>The work was significantly shaped by <strong>Valentina Serianni from Hana Cahová’s team</strong>, who demonstrated the ability of dinucleoside polyphosphates to initiate gene transcription, and by <strong>Jana Škerlová</strong>, 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.</p><p>Hana Cahová adds: <i>“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.”</i></p><p><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"></p><div><p>Cryogenic electron microscopy (cryo-EM) was central to the project. This part of the work was led by<strong> Dr. Tomáš Kouba</strong>, one of the authors of the study. <i>“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,”</i> he explains.</p><p>Last year, IOCB Prague opened a new <a target="_blank" rel="noopener noreferrer" href="https://cryoem.group.uochb.cz/en"><strong>cryo-EM center</strong></a><strong> </strong>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.</p><p><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"></p><blockquote><h4><strong>The Original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41589-025-02134-5"><strong>Molecular insight into 5′ RNA capping with Np<sub>n</sub>Ns by bacterial RNA polymerase</strong></a></h4><p>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;</p><p>Nat. Chem. Biol. 21 (2026)</p><p><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></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><h4><strong>Abstract</strong></h4><p>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 <i>Thermus</i> <i>thermophilus</i>. 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.</p></div></div>

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

<p><strong>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.</strong></p><blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars"><strong>👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</strong></a></h4><p><strong>👉 Search and filter in the largest global database</strong> with over <strong>5 000 GC, LC, MS and spectroscopy webinars</strong>.</p></blockquote><div><div><div><div><div><div><h5><strong>1. Thermo Fisher Scientific: Process Raman – A Reliable and Versatile Tool for Downstream Process Monitoring and Control for mAb Production</strong></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><p>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.</p><h5><strong>2. Wasson-ECE Instrumentation: The Data Driven Plant – How AI Transforms Chemical Manufacturing</strong></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><p>Explore how artificial intelligence is applied to improve process efficiency, monitoring, and decision-making in modern chemical manufacturing.</p><h5><strong>3. New Food Magazine: The Science of Next-Gen Ingredients – Fermentation, Formulation and Function</strong></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><p>Discover how fermentation-driven innovation is transforming functional food ingredients, with analytical insights to optimize flavour, functionality, and product stability.</p></div></div></div></div></div></div>

Webinars LabRulezGCMS Week 07/2026

<p><strong>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.</strong></p><p>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.</p><blockquote><h4><strong>The original article</strong></h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360"><strong>QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans</strong></a></h4><p>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*</p><p>ACS Omega 2025, 10, 51, 63464–63473</p><p><a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsomega.5c10360">https://doi.org/10.1021/acsomega.5c10360</a></p><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/"><strong>CC-BY 4.0</strong></a></h6></blockquote><p><strong>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.</strong></p><p>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></p><p>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></p><p>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.</p><p>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/Na<sub>2</sub>SO<sub>4</sub> 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-NH<sub>2</sub> 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 MgSO<sub>4</sub> for pyrethroids, followed by GC ECD and GC–MS.</p><p>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.</p><h4><strong>Experimental Section</strong></h4><h5><strong>Instrumental Apparatus</strong></h5><p>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"><strong>GC-MS-QP2010SE</strong></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"><strong>AOC-20i autosampler</strong></a>. Separation was achieved using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-5MS"><strong>Agilent DB-5MS capillary column</strong></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>.</p><p>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>.</p><p><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"></p><h5><strong>Application of the Proposed Procedure to Real Samples</strong></h5><p>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 Na<sub>2</sub>SO<sub>4</sub> in a 1:1 w/w ratio) was added, followed by an aliquot of the atrazine-<i>d</i><sub>5</sub> solution (surrogate standard) to yield a final concentration of 250 μg kg<sup>–1</sup>. 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>).</p><p><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"></p><h4><strong>Results and Discussion</strong></h4><h5><strong>Evaluation of the Effect of Low and Ultralow Temperatures on the Analytical Response</strong></h5><p>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.</p><p>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.</p><p><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"></p><h5><strong>Application to Real Samples</strong></h5><p>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<sup>–1</sup>. These values are below the MRL established by European Union regulation, which is 100 μg kg<sup>–1</sup>. <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.</p><p><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"></p><p>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<sup>–1</sup>. 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.</p><h4><strong>Conclusions</strong></h4><p>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.</p><p>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.</p><p>The pyrethroid permethrin was quantified in four cocoa samples. However, the concentrations did not exceed the MRL established by European Union legislation.</p><p>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.</p>

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. 

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<p><strong>In this session, discover how Wiley’s KnowItAll saves hours of GC-MS manual analysis time by combining fast, flexible deconvolution with an integrated reference database search into a single, automated workflow to identify components.</strong></p><h4>We will demonstrate through a series of live examples:</h4><ul><li><strong>KnowItAll’s various methods for GC-MS analysis and how they can impact your workflow.</strong></li><li><strong>Professors and students engaged in chemistry and mass spectrometry courses or lab work.</strong></li></ul><p>About KnowItAll: KnowItAll combines all the tools and spectral databases you need for effective analysis into a single, easy-to-use interface to make your lab its most efficient. Compatible with over 130 instrument formats, it streamlines your entire workflow regardless of how many techniques and instruments you use. Learn more at sciencesolutions.wiley.com</p><blockquote><p><strong>Presenter: </strong>Dr. Leanna Ergin (Associate Editor, Wiley Science Solutions)</p><p>Dr. Leanna Ergin is an Associate Editor for Wiley Science Solutions, for which she helps create tools for spectroscopy, structural, and scientific standard reference data and helps create innovative software applications. Leanna completed her PhD in Clinical-Bioanalytical Chemistry from Cleveland State University, where she developed a protocol for processing hyperspectral image data that distinguishes the spectra, removes degeneracies caused by symmetry, and is generalized to work with any number of wavelength dimensions and spectra. The results are mapped to the full RGB colorspace of modern computer displays. Leanna joined Wiley in 2022.</p><p><strong>Presenter:&nbsp;</strong>Dr. Michelle D’Souza (Product Manager, Software Products, Wiley Science Solutions)</p><p>Dr. D’Souza has over 15 years of experience in the management and development of spectroscopy software, including her current position as product manager for software products at Wiley Science Solutions and prior to that at Bio-Rad Laboratories, Inc. She also worked many years in the pharmaceutical industry after obtaining a Ph.D. in chemistry from Northern Illinois University.</p></blockquote>

The Analytical Scientist: Introduction to KnowItAll for Mass Spectrometry

Introduction to KnowItAll for Mass Spectrometry

How Wiley’s KnowItAll saves hours of GC-MS manual analysis time.

<p><strong>We’ll explore how outlier setup can help you focus on samples and compounds that require your attention, ensuring accurate and reliable results.</strong></p><p>Additionally, you’ll learn how viewing compounds and calibration at a glance can expedite data review, making the process faster and more intuitive.</p><p>Finally, we’ll demonstrate how easily you can summarize your results in comprehensive reports or export them to Excel, streamlining your workflow and enhancing productivity.</p><p>Don’t miss this opportunity to enhance your data analysis skills with MassHunter Quant!</p><blockquote><p><strong>Presenter:</strong> Peter Kornas (LC/MS Applikationsspezialist, Agilent Technologies)</p><p>Peter Kornas has more than 10 years of experience in the development and validation of analytical methods for the determination of pesticides, mycotoxins and contaminants using LC/MS/MS. Before joining Agilent as an LC/MS application specialist in 2018, he worked as an analytical chemist in the food industry. During this time, he was responsible for the development and validation of analytical methods and worked in close coordination with Regulatory Affairs to ensure compliance with the legal requirements of the LC/MS method portfolio.</p></blockquote>

Agilent Technologies: MassHunter Masterclass Months

MassHunter Quant – A Fast and Easy Way from Data to Results

Join us and discover how quickly a quantitation method can be set up, enabling efficient data processing.

<p><strong>Join us for an insightful webinar where we will explore the critical aspects of differentiating good from bad data and how this distinction can significantly influence your results. From screening to quantification, discover the value of targeted data analysis workflows using non-targeted data with our innovative software and hardware.</strong></p><p>Find by Formula algorithm. Learn to identify the most suitable MS/MS approach for your experiments, initiate quantitation for your compounds of interest, and incorporate retention times (RTs) and MS/MS spectra into a custom database and library.</p><p>This session is designed to enhance your understanding and application of Q-TOF data analysis, ensuring robust and reliable outcomes.</p><blockquote><p><strong>Presenter:</strong> Hannah Florance (Agilent Technologies)</p><p>Hannah has had multiple roles in the life sciences, starting as a protein chemist, before moving into proteomics and then metabolomics. A major part of her time working in academia involved running LC and GCMS core facilities supporting projects ranging from synthetic biology to cancer research. She is currently an LCMS applications specialist for Agilent.<br><br><strong>Presenter:</strong> Stefan Schaebler (Application Specialist LC/MS, Agilent Technologies)</p><p>Stefan completed his PhD in Biology, specializing in LC-MS-based lipidomics and metabolomics. Following his doctoral studies, he joined Agilent Technologies as an LC/MS Application Specialist. In this role, Stefan focuses on small molecule applications using LC-QTOF, with a strong emphasis on software tools and data interpretation.</p></blockquote>

MassHunter Qual – The Solid Pillar in Q-TOF Data Analysis

We will explore the critical aspects of differentiating good from bad data and how this distinction can significantly influence your results.

<div><p><strong>In this session, discover how Wiley’s KnowItAll saves hours of GC-MS manual analysis time by combining fast, flexible deconvolution with an integrated reference database search into a single, automated workflow to identify components.</strong></p><p><strong>We will demonstrate through a series of live examples:</strong></p><ul><li>KnowItAll’s various methods for GC-MS analysis and how they can impact your workflow.</li><li>Professors and students engaged in chemistry and mass spectrometry courses or lab work.</li></ul><p><strong>About KnowItAll: </strong>KnowItAll combines all the tools and spectral databases you need for effective analysis into a single, easy-to-use interface to make your lab its most efficient. Compatible with over 130 instrument formats, it streamlines your entire workflow regardless of how many techniques and instruments you use. Learn more at sciencesolutions.wiley.com</p><blockquote><p><strong>Presenter:</strong> Dr. Leanna Ergin (Associate Editor, Wiley Science Solutions)</p><p>Dr. Leanna Ergin is an Associate Editor for Wiley Science Solutions, for which she helps create tools for spectroscopy, structural, and scientific standard reference data and helps create innovative software applications. Leanna completed her PhD in Clinical-Bioanalytical Chemistry from Cleveland State University, where she developed a protocol for processing hyperspectral image data that distinguishes the spectra, removes degeneracies caused by symmetry, and is generalized to work with any number of wavelength dimensions and spectra. The results are mapped to the full RGB colorspace of modern computer displays. Leanna joined Wiley in 2022.</p><div><strong>Presenter:</strong> Dr. Michelle D’Souza (Product Manager, Software Products, Wiley Science Solutions)</div><p>Dr. D’Souza has over 15 years of experience in the management and development of spectroscopy software, including her current position as product manager for software products at Wiley Science Solutions and prior to that at Bio-Rad Laboratories, Inc. She also worked many years in the pharmaceutical industry after obtaining a Ph.D. in chemistry from Northern Illinois University.</p></blockquote></div>

Discover how Wiley’s KnowItAll saves hours of GC-MS manual analysis time by combining fast, flexible deconvolution with an integrated reference database

<div><div id="inner_content_body_text" data-content-id="391110"><p><strong>Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals prevalent across numerous industries and used in many everyday products, but their persistent and bioaccumulative nature raises critical health and environmental concerns. Join us for our upcoming Ask Me Anything (AMA) Q&amp;A session, where you can explore the latest research, regulatory challenges and advancements in the field.</strong></p><p>During this hour-long virtual session, you’ll have the unique opportunity to ask your most pressing questions directly to our expert speaker, Dr. Ian Ross, in real time.</p><h4><strong>About Our Expert</strong></h4><p>We are honored to host Dr. Ian Ross, Global PFAS Practice Lead at CDM Smith and visiting professor at Manchester Metropolitan University. Dr. Ross is a distinguished biochemist specializing in contaminated land assessment and PFAS decontamination. His extensive expertise is reflected in over 100 publications, including a comprehensive 204-page chapter on PFAS in the Emerging Contaminants Handbook.</p><h4><strong>What to Expect</strong></h4><p>Ian will connect with our live audience to address a broad spectrum of topics related to PFAS. While the spontaneous nature of an AMA session makes it impossible to predict every question, we anticipate discussions will focus on:</p><ul><li><strong>PFAS contamination:</strong> Latest research and case studies</li><li><strong>Environmental and health impacts:</strong> Emerging evidence and implications</li><li><strong>Regulatory challenges: </strong>Current frameworks and future directions</li><li><strong>Applications and concerns:</strong> Industrial uses and associated risks</li></ul><div><div><h4><strong>Why Attend?</strong></h4></div></div><ul><li><strong>Expert insights:</strong> Gain knowledge directly from a leading authority in PFAS.</li><li><strong>Live interaction:</strong> Have your questions addressed in real time for personalized answers.</li><li><strong>Exclusive content:</strong> Access in-depth discussions that you won't find anywhere else.</li></ul><p><strong>Space is limited! Register now to secure your spot for this exclusive AMA session.</strong></p><p><span><strong>Presenter:</strong> Ian Ross, PhD </span>(CDM Smith / Global PFAS Practice Lead, Manchester Metropolitan University)</p></div></div>

Technology Networks: Ask Me Anything: PFAS

Ask Me Anything: PFAS

Ian will connect with our live audience to address a broad spectrum of topics related to PFAS.

<p><strong>Sample preparation plays a significant role in GC–MS analysis, with various approaches available to enhance analytical sensitivity and provide a more comprehensive sample profile. Understanding the science behind microextraction techniques, such as SPME and sorptive extraction, enables chemists to optimize methods for challenging matrices, thus uncovering more from your sample.</strong></p><p>In this webinar, Professor Elia Psillakis from the Technical University of Crete will explore advanced sample preparation techniques for GC–MS. She will focus on evolving microextraction methods, including SPME, thin-film SPME, SPME Arrow, vacuum-assisted SPME, and HiSorb. Professor Psillakis will discuss the fundamentals of these extraction techniques and explain how a deeper understanding of the sample preparation workflow can lead to improved qualitative and quantitative GC–MS analysis, resulting in more accurate and efficient extractions.</p><p><strong>By attending this presentation, you will:</strong></p><ul><li>Understand the core scientific principles behind micro-extraction methods for GC–MS, including SPME and high-capacity extraction techniques</li><li>See how SPME is used in various applications, and how advanced sample concentration techniques can extend the scope of your analysis</li><li>Explore how vacuum-assisted extraction technologies improve sensitivity and efficiency in the analysis of complex samples</li></ul><blockquote><p><strong>Presenter:</strong> Elia Psillakis (Professor, Aquatic Chemistry Laboratory, Technical University of Crete)</p><p>Elefteria (Elia) Psillakis is a Professor in Water Chemistry at the School of Chemical and Environmental Engineering, Technical University of Crete, Greece. She is Editor-in-Chief of the Journal "<i>Advances in Sample Preparation</i>", Elsevier, Head of the Sample Preparation Network of the EuChemS-Division of Analytical Chemistry, and the Founder and Director of ExtraTECH Analytical Solutions, a spin-off company of the Technical University of Crete. From 2014–2016, she was the Vice Rector of Academic Affairs and Research at the Technical University of Crete.</p><p><strong>Presenter:</strong> Lucy Hearn (Application Specialist, Markes International)</p><p>Lucy Hearn received an MSc in Green Chemistry and sustainable industrial technologies from the University of York, UK, where her final-year project focused on the extraction and isolation of cannabinoids from hemp using supercritical CO<sub>2</sub> and Starbons. She later took up the role of application specialist at Markes, providing technical and application support to users around the world and developing applications using extraction and enrichment techniques for GC–MS.</p></blockquote>

Separation Science: Sorptive Extraction Fundamentals and Applications: Extracting More with SPME and HiSorb

Sorptive Extraction Fundamentals and Applications: Extracting More with SPME and HiSorb

We will focus on evolving microextraction methods, including SPME, thin-film SPME, SPME Arrow, vacuum-assisted SPME, and HiSorb.

Extracting More with SPME and HiSorb

<p><strong>Hear about the latest advancements in translational proteomics and metabolomics. From the molecular mechanisms of disease pathology to the latest technological developments in diagnostics and treatment.</strong></p><h5><strong>Key Learning Objectives:</strong></h5><ul><li>Spatial proteomics to assess health and diseases</li><li>Absolute quantitation of human proteins</li><li>The latest innovations in proteomics and metabolomics instrumentation and data analysis</li><li>Biomarker-guided precision medicine</li></ul><h4><strong>Day 2 – October 31</strong></h4><h5><strong>15:00 – 15:50 GMT: A Novel Strategy for the Absolute Quantification of Human Proteins</strong></h5><ul><li>Christoph Borchers, PhD (McGill University)</li></ul><h5><strong>15:50 – 15:55 GMT: </strong>Networking Break</h5><h5><strong>15:55 – 16:15 GMT: From Single Cells to the Metaproteome: Latest Developments in timsTOF Technology for Proteomics</strong></h5><ul><li>Matt Willetts, PhD (Bruker)</li></ul><h5><strong>16:15 – 16:20 GMT: </strong>Networking Break</h5><h5><strong>16:20 – 17:10 GMT: Single-Cell Chromatin Proteomics to Investigate the Biology of Exceptional Longevity</strong></h5><ul><li>Simone Sidoli, PhD (Albert Einstein College of Medicine)</li></ul><h5><strong>17:10 – 17:15 GMT: </strong>Networking Break</h5><h5><strong>17:15 – 17:35 GMT: Optimizing Metabolomics Workflows: From Sample Preparation to Multi-omics Integration</strong></h5><ul><li>Hagen Magnus Gegner, PhD (CTC Analytics)</li></ul><h5><strong>17:35 – 17:40 GMT:</strong> Networking Break</h5><h5><strong>17:40 – 18:10 GMT: Analyzing Metabolic Responses to a Standardized Meal Challenge Using Exhaled Breath</strong></h5><ul><li>Matteo Tardelli, PhD (Owlstone Medical)</li></ul><h5><strong>18:10 GMT: </strong>Event Close</h5><h5><strong>Who Should Attend:</strong></h5><ul><li>Scientists and researchers seeking to expand their knowledge</li><li>Pharmaceutical and biotech professionals driving drug development</li><li>Clinicians looking to improve patient care</li><li>Academicians exploring new research avenues</li><li>Graduate students and postdoctoral fellows building their careers</li></ul><blockquote><p><strong>Presenter: </strong>Mathias Uhlén, PhD (Professor, KTH - Royal Institute of Technology)</p><p><strong>Presenter:&nbsp;</strong>Christoph Borchers, PhD (Professor, McGill University)</p><p><strong>Presenter:</strong>&nbsp;Janne Lehtiö, PhD (Professor, Karolinska Institutet)</p><p><strong>Presenter:</strong>&nbsp;Crystal Montoya (Senior Marketing Product Manager, Miltenyi Biotec)</p><p><strong>Presenter:</strong>&nbsp;Kari Basso, PhD (Director of Mass Spectrometry Research and Education, University of Florida)</p><p><strong>Presenter:&nbsp;</strong>Fabian Coscia, PhD (Group Leader, Max Delbrück Center)</p><p><strong>Presenter:</strong>&nbsp;Simone Sidoli, PhD (Assistant Professor, Albert Einstein College of Medicine)</p><p><strong>Presenter:</strong>&nbsp;Hagen Magnus Gegner, PhD (Content and Digital Marketing, CTC Analytics)</p><p><strong>Presenter:</strong>&nbsp;Matt Willetts, PhD (Proteomics Applications Manager, Bruker Daltonics)</p><p><strong>Presenter:&nbsp;</strong>Matteo Tardelli, PhD (Senior Biomarker Scientist, Owlstone Medical)</p><p><strong>Presenter:&nbsp;</strong>Aaron Gajadhar, PhD (Director, Strategic Applications, Seer)</p><p><strong>Presenter:&nbsp;</strong>Gary Siuzdak, PhD (Professor and Senior Director, Scripps Research Institute)</p></blockquote>

Technology Networks: Advances in Proteomics & Metabolomics 2024

Advances in Proteomics & Metabolomics 2024 (Day 2)

Hear about the latest advancements in translational proteomics and metabolomics. 

Advances in Proteomics & Metabolomics 2024  (Day 1)

<div id="inner_content_body_text" data-content-id="391734"><p><strong>Join us for an exclusive, extended webinar spotlighting the cutting-edge innovations propelling the future of battery research and development. This immersive webinar features multiple talks, offering a comprehensive exploration of the groundbreaking advancements in materials and technologies that will transform energy storage.</strong><br><br>Led by industry experts, sessions will provide deep insights into the latest breakthroughs, showcasing how these innovations are shaping the future of battery technology and driving transformative change in energy solutions.<br><br><strong>Attend this webinar to:</strong></p><ul><li>Understand the challenges of using silicon in lithium-ion batteries</li><li>Explore the role of conductive polymer binding in battery performance</li><li>Discover how hyphenating technologies can provide deeper insights into complex materials for battery research</li></ul><blockquote><p><strong>Presenter:</strong> Krystelle Mafina, PhD (Applied Products Leader, PerkinElmer)</p><p><strong>Presenter:</strong> Gao Liu, PhD (Senior Scientist and Group Leader, Lawrence Berkeley National Laboratory)</p></blockquote></div>

Technology Networks: Innovative Technologies and Materials Advancing Battery Research

Innovative Technologies and Materials Advancing Battery Research

A comprehensive exploration of the groundbreaking advancements in materials and technologies that will transform energy storage.

Technologies and Materials Advancing Battery Research

<div pardot-region="webinar-information" pardot-region-type="pardot" id="description" data-id="29767" data-hml-enabled="1"><p><strong>LECO will regularly invite key leaders of the NTS space from all industries to present and discuss their groundbreaking work. This series promises not only to delve deeper into the intricacies of non-targeted screening but also to foster collaboration and knowledge exchange among experts and enthusiasts alike. Secure your spot now and embark on a journey of discovery in chemical analysis, with each instalments of our monthly webinar series delivering fresh perspectives and invaluable insights.</strong></p></div><div pardot-region="speaker-information" pardot-region-type="pardot" id="speakers" data-id="29770" data-hml-enabled="1"><div><div><p>In his talk, Prof. Zoccali&nbsp;will explore the pioneering applications of Comprehensive Two-Dimensional Gas Chromatography coupled with Time-of-Flight Mass Spectrometry in the analysis of extra virgin olive oil (EVOO), measured on our newly released Pegasus BTX GCxGC-ToF MS.</p><p>He will demonstrate how this advanced technique provides insights in both targeted and non-targeted analyses , offering deeper understanding&nbsp;into EVOO's chemical profiles. Dr. Zoccali will also highlight how GCxGC-ToF MS enhances the detection of contaminants and key compounds, such as antioxidants and sterols, which are essential for assessing quality, authenticity and flavor.</p><p>Don't miss this opportunity to gain valuable knowledge from an expert in food analysis.&nbsp;</p><blockquote><p><strong>Presenter:</strong> Professor. Mariosimone Zoccali (University of Messina, Italy)</p><p>Joining us from the University of Messina, Mariosimone Zoccali, Assistant Professor of Analytical Chemistry, will present on 'Boosting Food Analysis Using GCxGC-ToFMS.&nbsp;</p></blockquote></div></div></div>

LECO: Non-Targeted Screening in Food: Boosting Food Analysis using GC×GC-ToF MS

Non-Targeted Screening in Food: Boosting Food Analysis using GC×GC-ToF MS

Applications of GCxGC coupled with TOF MS in the analysis of extra virgin olive oil (EVOO), measured on our newly released Pegasus BTX GCxGC-ToF MS.

Boosting Food Analysis using GC×GC-ToF MS

<p><strong>Who Should Attend:</strong></p><ul><li>Anyone who would like to gain more knowledge on PAH analysis with GC columns&nbsp;</li><li>Any scientists who is struggling with resolution on PAHs with GC analysis</li></ul><p><strong>Key Learning Points:</strong></p><ul><li>Learn about columns with different selectivities in PAH analysis&nbsp;</li><li>Understand the pain point in PAH analysis in food and environmental industry</li><li>Find what are the parameters to adjust to improve the resolution in GC&nbsp;</li></ul><blockquote><p><strong>Presenter:</strong> Grace Guo (Senior Technical Specialist, Phenomenex)</p><p>Grace Guo graduated from the Johns Hopkins University with a Master’s degree in Material Science and Engineering. She joined Phenomenex Technical Team in 2017 providing technical support globally. With more than 8 years of experience on SPE, HPLC and GC, she delivered 50+ seminars and webinars globally covering food and environmental, clinical, pharma and biopharma industry.&nbsp;</p></blockquote>

GC Column Selectivities for PAH Compounds

MassHunter Qual – The Solid Pillar in Q-TOF Data Analysis

Innovative Technologies and Materials Advancing Battery Research

Advances in Proteomics & Metabolomics 2024 (Day 2)

Non-Targeted Screening in Food: Boosting Food Analysis using GC×GC-ToF MS

Ask Me Anything: PFAS

Introduction to KnowItAll for Mass Spectrometry

Introduction to KnowItAll for Mass Spectrometry

MassHunter Quant – A Fast and Easy Way from Data to Results

Sorptive Extraction Fundamentals and Applications: Extracting More with SPME and HiSorb

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