<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

Article

Webinars

Food

Scientific article

Science and research

Video

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

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

LabRulez

Separation Science

Agilent Technologies

ACD/Labs

LECO

Wiley

C&EN

Waters Corporation

<p><strong>Discover how you can save hours of manual GC-MS analysis time.</strong></p>
<p>High-resolution GC-MS data are information rich. As a result, analysis can be time-consuming, especially if you’re examining complex analytes. That’s where KnowItAll’s MS Expert comes in. Find out how this new system will save you time by combining  fast, flexible deconvolution with reference database search into a single, automated workflow to identify components. </p>
<h5><strong>In this session, discover with the help of live examples:</strong></h5>
<ul>
<li><p>How the system quickly deconvolutes the GC-MS data file and automatically presents search results for each extracted component in a single shot – so you don’t need to manually search each component individually against the reference database.</p>
</li>
<li><p>How unidentified components can then be sent through KnowItAll’s workflow to the patented MS Adaptive Search for further analysis to deduce structural components.</p>
</li>
</ul>
<blockquote>
<p><strong>Presenter:</strong> Michelle D’Souza, Ph.D. (Product Manager, Software Products, Wiley Science Solutions)</p>
</blockquote>
<blockquote>
<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 for many years in the pharmaceutical industry after obtaining a Ph.D. in chemistry from Northern Illinois University.</p>
</blockquote>


Wiley: Automate GC-MS analysis with KnowItAll MS Expert

Automate GC-MS analysis with KnowItAll MS Expert

Discover how you can save hours of manual GC-MS analysis time.

<p><strong>Questions that are answered by structure elucidation and &amp; verification are integral parts of chemical R&amp;D workflows from discovery to development and manufacturing. But as scientists constantly strive to do their work faster and better, they must be careful to ensure that efficiency does not come at the cost of confidence in the determined structure.</strong></p>
<p>Join us as we bring together experts from some of the industry’s leading organizations to share how they leverage software to make the most of their NMR, LC/MS, and GC/MS data and boost their structure elucidation and verification workflows.</p>
<h5>Who won’t want to miss this symposium?</h5>
<ul>
<li><p>Synthetic and medicinal chemists responsible for elucidating and verifying the structures of their reaction products and by-products<br/>Natural products researchers</p>
</li>
<li><p>Members of structure elucidation groups</p>
</li>
<li><p>Decision makers at institutions where chemical structures need to be identified quickly and confidently</p>
</li>
</ul>
<h3><strong>Event Agenda</strong></h3>
<h5><strong>15:30-16:10 (CEST) Combined LC/MS and NMR for Automated Verification of Chemical Structures</strong></h5>
<ul>
<li><strong>Celine Nguyen-Van-Dau</strong> (Head of Integrated Drug Discovery (IDD) Structural Analysis team, Sanofi)</li>
</ul>
<h5><strong>16:15-16:50 (CEST) Pharmaceutical Discovery and Development Analytical Workflows</strong></h5>
<ul>
<li><strong>Kevin Robbins</strong> (Associate Principle Scientist, AstraZeneca)</li>
</ul>
<h5><strong>16:55-17:30 (CEST) Conformational Analysis of Peptidomimetic Drug Leads by NMR</strong></h5>
<ul>
<li><strong>Purnima Khandelwal</strong> (Senior Principal Scientist, Small Molecule Drug Discovery, Bristol Myers Squibb)</li>
</ul>
<h5><strong>Hosted By</strong></h5>
<ul>
<li><strong>Sanji Bhal</strong> (Director, Marketing Communications (ACD/Labs))</li>
<li><strong>Sarah Srokosz</strong> (Marketing Communications Specialist (ACD/Labs))</li>
</ul>


ACD/Labs: What's That Peak? Structure Elucidation & Verification Virtual Symposium 

What's That Peak? Structure Elucidation & Verification Virtual Symposium

What’s in my sample? Did I make what I think I made? What’s that peak?

What's That Peak? Structure Elucidation & Verification

<p><strong>According to the PIC/S guidance complex or open-ended processes that lead to subjective interpretation, can result in an increase in data failures.  One way to reduce this risk is with a simplified, well-defined process.  Empower software enables you with tools to create structure in your chromatographic processes and workflow.  Leveraging a well-defined workflow along with a clear SOP that details important steps, such as how to work thru reprocessing of data, will reduce the risk of failures.  More complexity added to a workflow can result in an increase in data review requirements and subsequently the associated audit trails.</strong></p>
<p>In this workshop we will define a chromatographic workflow with Empower software to support data integrity goals.  Starting with method development, method validation, and routine usage to data acquisition, data processing, reporting results, and using control charts to track and trend data.  </p>
<p>Please join us for this live discussion to learn more and bring your Empower software questions for this exclusive opportunity to ask our expert, Neil Lander, anything about Empower CDS!</p>
<blockquote>
<p><strong>Presenter:</strong> Neil Lander (Principal Product Manager, Waters Corporation)</p>
</blockquote>
<blockquote>
<p>Neil has worked for Waters Corporation since 1994 and has held a variety of positions including Technical Support Specialist, Technical Trainer, Manager Customer Education and currently, Principal Marketing Manager focusing on Informatics solutions. He provides internal support for Empower Chromatography Data System and is focused on developing laboratory software solutions that help organizations achieve their scientific and operational objectives. Prior to joining Waters, he was an analytical chemist where he gained experience in both the cosmetics and specialty chemical industries.</p>
</blockquote>


Waters Corporation: Empower Tips: Ask Me Anything About Creating Efficiency in Your Routine Workflow with Simple Automation Steps

Empower Tips: Ask Me Anything About Creating Efficiency in Your Routine Workflow with Simple Automation Steps

In this workshop we will define a chromatographic workflow with Empower software to support data integrity goals.

Empower Tips: Simple Automation Steps

<p><strong>Event Overview: Pesticide analysis can feel like an uphill battle: an ever-expanding list of target compounds, increasingly stringent regulations that drive lower detection limits, and constantly evolving sample matrices make it challenging to keep up. Agilent&#39;s multi-class, multi-residue methods based on LC/MS and GC/MS, give you a leg up on routine monitoring, enabling high throughput, sensitive detection levels, and rapid quantitative analysis for hundreds of pesticides in a single sample.</strong></p>
<p>Bring all your questions to be answered during our “Ask the Experts” panel. Join Agilent application scientists and engineers who will be available to provide guidance and expertise for all your hardware, software, and application related questions. </p>
<h5>This day will be dedicated to pesticide work using GCMS. Some topics to be discussed are:</h5>
<ul>
<li>Sample clean up in complex matrices: QuEChERS and beyond</li>
<li>Analyte enrichment out of aqueous matrices</li>
<li>GCMSMS acquisition settings for pesticides</li>
<li>Introduction to HydroInert source for H2 carrier gas</li>
<li>Converting your pesticides analysis to retain retention times or make the analysis faster</li>
<li>Full scan data analysis utilizing deconvolution for higher confidence with library matches</li>
<li>MRM Optimizer for transition creation and optimization</li>
</ul>
<blockquote>
<p><strong>Presenter:</strong> Tina Chambers (Sample Prep Application Scientist, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Tina started her career in Analytical Chromatography with Varian in 2002 and spent the first five years providing technical support for their LC columns, GC columns and sample preparation portfolios. After three years in sales, she returned to her technical roots with Agilent in 2010, consulting with customers on efficient and optimized sample preparation strategies.</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Rachael Ciotti (GC/MS Application Specialist, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Rachael Ciotti is a GCMS Application Specialist at Agilent Technologies in Wilmington, DE. Previously, she was a Field Service Engineer specializing in installing, maintaining, and repairing Agilent GC and GC/MS systems. Prior to joining Agilent, Rachael worked at DuPont as an analytical chemist responsible for GC and GC/MS method development and transfer to manufacturing labs. She holds a Bachelor of Arts in Mathematics from Rutgers University.</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Matt Curtis, PhD (GC/MS Applications Scientist, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Matt joined Agilent in 2013 as a GC/MS applications scientist in the Santa Clara, CA Center of Excellence. His primary responsibility is focused on providing instrument demos for customer interested in each technology Agilent offers; the GC/MS single quadrupole, triple quadrupole and the quadrupole Time-of-Flight. The variety of different samples submitted to the demo lab provide a unique knowledge of optimizing parameters for different applications to provide the best quality data from the instrument.</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Angela Smith, PhD (Applications Chemist for GC and MS Supplies, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Angie is an applications chemist for GC and MS Supplies at Agilent Technologies in Wilmington, DE. Previously, she was an Applications Chemist for the MSD Solutions and Applications group with a focus on developing analyzers and applications for energy, chemical and environmental markets. She holds a Ph.D. in Physical Chemistry from Lehigh University and B.S. in Chemistry from Juniata College.</p>
</blockquote>


Agilent Technologies: Ask the Experts Panel: Pesticides by GC/MS

Ask the Experts Panel: Pesticides by GC/MS

Join Agilent application scientists who will be available to provide guidance and expertise for all your hardware, software, and application related questions.

<p><strong>Over the last two and a half years, we’ve all had to learn to communicate and work in new ways. With the help of technology, we’ve connected with colleagues across the globe in ways we never thought possible.  The ability to work remotely has ensured continued quality management of products consumed daily. For an analytical chemist or lab manager, quality management may include reviewing and approving data from the safety of your office whether in the lab or at home. No matter where the data is reviewed, completeness, accuracy and traceability must be maintained. This can be accomplished with a secure and efficient software platform.</strong></p>
<p>During this webinar, Kerri-Ann Blake, Product Manager for Titration, and Daniel Schmidt, IT Systems Engineer, will introduce you to the OMNIS data management platform. They will discuss how you can securely implement the software, review and sign data. You’ll learn how to track it all via audit trail from anywhere in the world - giving you peace-of-mind that all your data is being kept safe. </p>
<h5>Key Learning Objectives</h5>
<ul>
<li><strong>Introduce OMNIS software’s seamless networking capability and user management system</strong></li>
<li><strong>Demonstrate convenient audit trail features with next level compliance and data integrity</strong></li>
<li><strong>Discuss system security and ease of implementation</strong></li>
</ul>
<h5>Who Should Attend</h5>
<ul>
<li>QC/QA, R&amp;D and Process Development Lab Managers and Users </li>
<li>Anyone performing titrations in a 21 CFR Part 11 Compliant Environment </li>
<li>Those interested in data security and integrity</li>
</ul>
<blockquote>
<p><strong>Presenter:</strong> Kerri-Ann Blake (Titration Product Manager, Metrohm USA)</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Daniel Schmidt (IT Systems Engineer, Metrohm USA)</p>
</blockquote>
<blockquote>
<p><strong>Presenter:</strong> Catherine Dold (Health &amp; Environment Writer, C&amp;EN Media Group)</p>
</blockquote>


C&EN: Peace-of-Mind with Secure Data Management

Peace-of-Mind with Secure Data Management

Kerri-Ann Blake, Product Manager for Titration, and Daniel Schmidt, IT Systems Engineer, will introduce you to the OMNIS data management platform.

<p><strong>FTIR is deployed in most pharmaceutical laboratories. As such, they have the same or very similar compliance requirements as other techniques, e.g., UV-Vis.</strong></p>
<p>This presentation will discuss 21CFR requirements and present how they are addressed by MicroLab software for the Cary 630 FTIR.</p>
<blockquote>
<p><strong>Presenter:</strong> Louis Tisinger, PhD (Application Engineer, Molecular Spectroscopy, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Louis (Lou) Tisinger has a Ph.D. in Analytical Chemistry from Miami University in Oxford Ohio, where his graduate research involved the study of ATR imaging and microscope performance in vibrational spectroscopy. Most of his career has been related to pre- and post-sales support of FTIR spectrometers, microscopes, imaging systems, and thermal analytical instruments, focusing on analyzing customer samples, demonstrations, post-sales training, troubleshooting, and R&amp;D.</p>
</blockquote>


Agilent Technologies: A Review of FTIR 21 CFR Compliance Requirements

A Review of FTIR 21 CFR Compliance Requirements

This presentation will discuss 21CFR requirements and present how they are addressed by MicroLab software for the Cary 630 FTIR.

<p><strong>With ever-increasing demands on your time, labor, and resources, optimizing your workflow is essential. Learn best approaches from GC-TOFMS experts to enhance your one- and two-dimensional gas chromatography applications (GC-MS and GCxGC-MS) in this collection of short webinars.</strong></p>
<h4><strong>Switching to Hydrogen Carrier Gas</strong></h4>
<p>With an open ion source design, using hydrogen as a carrier gas for gas chromatography can save both time and money. Analyses are quicker, data quality is effectively the same, and a renewable hydrogen generator can slash the cost of helium. See examples of 1D and 2D method transfer, time savings, and real-life examples of data quality for various environmental and aroma applications in this webinar.</p>
<h4><strong>GC-MS Analysis Workflow</strong></h4>
<p>Small time savings throughout the workflow can add up to big savings. See aroma and flavor examples of how automated sample prep and elevated Time-of-Flight Mass Spectrometry (TOFMS) analysis, followed by software solutions to compare and evaluate data and results, can save your lab time and resources.</p>
<ul>
<li>Part I: ChromaTOF® Sync for GC-MS Analysis</li>
<li>Part II: ChromaTOF Tile for GCxGC-MS Analysis</li>
</ul>
<h4><strong>Discovery Workflow Best Practices</strong></h4>
<p>When you don&#39;t know what you&#39;re looking for, as is often the case with environmental contaminants and pollutants, the task can seem daunting, but high-resolution TOFMS and GCxGC is a powerful combination for non-target searches. With the tools included with the Pegasus® HRT+4D and the Multi-Mode Source™ (MMS™), identification of unknowns can be vastly improved and assigned higher confidence.</p>


LECO: Enhanced GC-MS Workflow Solutions Webinar

Enhanced GC-MS Workflow Solutions Webinar

Learn best approaches from GC-TOFMS experts to enhance your one- and two-dimensional gas chromatography applications (GC-MS and GCxGC-MS).

<p><strong>How do you know if your peak is “pure”? How do you know if your sample conforms to your gold standard? OpenLab CDS provides the tools to answer these questions. This seminar will show you how.</strong></p>
<blockquote>
<p><strong>Presenter:</strong> Richard Mutkoski (Laboratory Informatics Application Engineer, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Richard Mutkoski has been a field representative for over 27 years for both hardware and software. In his current role as an Informatics Application Engineer, Rich presents technical solutions of the OpenLab suite of products to customers worldwide. Prior to his tenure at Agilent Rich spent 15 years in a variety of Pharma QA/QC and R&amp;D positions providing him a unique understanding of those workflows, bottlenecks and challenges.</p>
</blockquote>


Agilent Technologies: Save Time Using the New Integration Optimizer in OpenLab CDS

Save Time Using the New Integration Optimizer in OpenLab CDS

How do you know if your peak is “pure”? How do you know if your sample conforms to your gold standard?

<p><strong>The growing demand for battery production has increased the importance for battery manufacturers to ensure that production workflows are efficient and cost-effective. With the complexity of battery manufacturing workflows, there is a high-value need to ensure that the performance and safety of pre-production testing of raw materials, in-process monitoring of intermediate components, and end-products meets specific industry standards.</strong></p>
<p>With the support of a modern laboratory information management system (LIMS), an organization can centrally organize the data generation through battery quality management workflows, and successfully access, analyze, and share data and information to increase time and efficiency. Implementing a LIMS can aggregate data in a meaningful way, seamlessly share that data, and drive insightful decision-making. With the right informatics tools to support production, battery manufacturers can build a strong foundation for improved quality and efficiency making sure that industry standards are met.</p>
<p>Attend this presentation to...</p>
<ul>
<li>discover how LIMS can improve traceability, data integrity, and efficiency in battery cell manufacturing workflows</li>
<li>learn what the benefits of implementing a LIMS into your battery manufacturing organization today would be.</li>
</ul>
<blockquote>
<p><strong>Presenter:</strong> Tareq Al-Najjar (Global Strategic Account Executive, Energy – Digital Science Solutions, Thermo Fisher Scientific)</p>
</blockquote>
<blockquote>
<p>Tareq has extensive experience identifying, establishing, and expanding market/product presence in the oil, gas, and energy arenas. With his most recent experience as the VP of International Business Development/Investor Relations at Vacom Systems LLC from 2015–2022, Tareq joined the Thermo Fisher Scientific team in February 2022 to bring his expertise into the LIMS sector. Tareq has a Bachelor of Science Degree in Electrical and Computer Engineering from the University of Utah and a Master of Business Administration (MBA) from the University of Utah David Eccles School of Business.</p>
</blockquote>


Separation Science: How LIMS can benefit battery manufacturing workflows

How LIMS can benefit battery manufacturing workflows

An upcoming presentation outlining the benefits of implementing a laboratory information management system into battery cell manufacturing workflows.

<p><strong>The new revision to Agilent&#39;s 8700 LDIR Software will be presented, showing new features for further simplification of workflows for analysis of microplastics.</strong></p>
<blockquote>
<p><strong>Presenter:</strong> Louis Tisinger, PhD (Application Engineer, Molecular Spectroscopy, Agilent Technologies, Inc.)</p>
</blockquote>
<blockquote>
<p>Louis (Lou) Tisinger has a Ph.D. in Analytical Chemistry from Miami University in Oxford Ohio, where his graduate research involved the study of ATR imaging and microscope performance in vibrational spectroscopy. Most of his career has been related to pre- and post-sales support of FTIR spectrometers, microscopes, imaging systems, and thermal analytical instruments, focusing on analyzing customer samples, demonstrations, post-sales training, troubleshooting, and R&amp;D.</p>
</blockquote>


Agilent Technologies: Improved Automated Microplastics Analysis Workflows

Improved Automated Microplastics Analysis Workflows

The new revision to Agilent's 8700 LDIR Software will be presented, showing new features for further simplification of workflows for analysis of microplastics.

GCMS webinars focusing on Software - page 20