<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. 

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

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<ul>
<li><strong>Common interface</strong> to visualize your data from different vendors.</li>
<li><strong>Automate all functionality</strong> such as data importing and display, integration, background subtraction, display of extracted mass chromatograms, molecule match, enumeration of molecular formula, etc.</li>
<li><strong>Verify proposed structures</strong> by automatically matching molecular ion and isotope peaks, and potentially the MS/MS fragmentation peaks.</li>
<li><strong>Predict the isotope clusters</strong> of a molecular formula with various adducts/losses and compare with observed mass spectrum.</li>
<li><strong>Process and report</strong> MS data on your computer, improves the efficiency and save time for more complex problems.</li>
<li><strong>Improve your efficiency</strong> by automating and customizing the analysis and reporting in batch mode or in real-time using Mnova scripts.</li>
<li>Make your <strong>analytical results searchable</strong> using Mnova DB!</li>
<li><strong>Calculate MS peak purity.</strong> The Mnova MS peak purity shows the curves associated to the most abundant mass peaks under the selected chromatogram peak.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Opens_the_power_of_the_technique_to_all_non_expert_users_9ccef334fa.jpg" alt="Mestrelab Research: Mnova MSChrom - Opens the power of the technique to all non-expert users."/></p>
<h3><strong>Mnova MSChrom Features</strong></h3>
<h4><strong>Background Subtraction</strong></h4>
<ul>
<li>This new feature is designed to facilitate background subtraction in your datasets, offering the capability to apply mass spectra and UV subtraction to lower impurities and noisy common peaks obtained from your analytical system, etc. to achieve more precise data analysis.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Sample_2_and_blank_1_used_to_apply_MS_Background_Subtraction_and_the_result_3_6a554048a8.jpg" alt="Mestrelab Research: Mnova MSChrom - Sample, 2, and blank, 1, used to apply MS Background Subtraction and the result, 3."/></p>
<h4><strong>New Enhanced Peak Picking Algorithm and Blind Regions</strong></h4>
<ul>
<li><p>Now, MSChrom includes a new <strong>Enhanced Peak Picking Algorithm</strong> providing an alternative to the Classic algorithm used in previous versions of MSChrom. Within <strong>Enhanced</strong> peak picking algorithm new settings are available to reproduce your best results in terms of detection and integration, including Baseline Correction, smoothing features, and a new functionality based on Saturated levels, where users can set an abundance threshold to identify those overloaded peaks due to detector saturation, and perform corrections on them.</p>
</li>
<li><p>Introducing the new <strong>Blind Regions</strong> tool-a highly beneficial addition. This tool enables the selective exclusion of those undesired regions from chromatograms during analytical processes as peak picking or any general data treatment. Blind Regions will remain ignored saving time, resources, providing better reproducible results. It proves especially helpful in cases where challenges arise in specific regions (solvent front in LC, column bleeding in GC, etc.) or, for instance, when opting to discard the limits of the chromatogram.</p>
</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Chromatographic_Peak_Detection_Settings_panel_and_Blind_Regions_table_displayed_after_peak_picking_9f4b2b6def.jpg" alt="Mestrelab Research: Mnova MSChrom - Chromatographic Peak Detection Settings panel and Blind Regions table displayed after peak picking process and applying two blind regions on the chromatogram."/></p>
<h4><strong>Combine NMR and LC-MS or GC-MS Data in the Same Document</strong></h4>
<ul>
<li>Automatically open analytical data from instruments like Agilent, Bruker, JEOL, Thermo, and Waters, along with data in mzData or mzXML formats (<a href="http://www2.mestrelab.com/l/271522/2024-04-10/3p2gs6"><strong>refer to supported formats here</strong></a>).</li>
<li>Integrate peaks in TIC, MS, and UV/ELSD traces, either automatically or manually.</li>
<li>Choose mass spectra based on TIC peaks, with or without background subtraction, and display them in either centroid or profile mode.</li>
<li>Manually co-add mass spectra, and seamlessly analyze and report NMR and MS data together in the same document</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Combine_NMR_and_LC_MS_or_GC_MS_Data_in_the_Same_Document_a575d33699.jpg" alt="Mestrelab Research: Mnova MSChrom - Combine NMR and LC-MS or GC-MS Data in the Same Document."/></p>
<h4><strong>Effortlessly Generate EMC/EIC, UV Traces, and UV Spectra</strong></h4>
<ul>
<li>Create Extracted Mass/Ion Chromatograms (EMC/EIC) within a specified mass range or at a particular m/z value.</li>
<li>Generate UV Traces effortlessly by selecting a wavelength from a DAD trace.</li>
<li>Easily extract UV spectra at chosen retention times from a PDA total absorbance chromatogram.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Effortlessly_Generate_EMC_EIC_UV_Traces_and_UV_Spectra_e80492edfa.jpg" alt="Mestrelab Research: Mnova MSChrom - Effortlessly Generate EMC/EIC, UV Traces, and UV Spectra."/></p>
<h4><strong>Automatic Molecule Matching for Structure Confirmation</strong></h4>
<ul>
<li>Beyond its extensive NMR structure confirmation tools within the NMR plugin, Mnova MSChrom introduces the molecular match feature, an invaluable resource for verifying structures through LC/GC/MS analysis.</li>
<li>This functionality is exceptionally swift and user-friendly, ensuring accessibility for all users, including those new to the field.</li>
<li>Import chemical structures and let the software automatically confirm matches with your experimental data. Customize match criteria by selecting adducts, losses, mass accuracy, score thresholds, etc.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Automatic_Molecule_Matching_for_Structure_Confirmation_04d66572d1.jpg" alt="Mestrelab Research: Mnova MSChrom - Automatic Molecule Matching for Structure Confirmation."/></p>
<h4><strong>Isotope Cluster Prediction for Elemental Composition Verification</strong></h4>
<ul>
<li>The feature enables users to propose one or multiple molecular formulas and anticipate their mass peaks using a predefined list of adducts or losses.</li>
<li>Mnova MSChrom generates a list of molecular ion and isotopic peaks, automatically aligning them with experimental peaks, if present.</li>
<li>Customize the display by choosing the desired prediction, along with the corresponding adduct or loss, for comparison on the spectrum.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Isotope_Cluster_Prediction_for_Elemental_Composition_Verification_7f75f9d6c3.jpg" alt="Mestrelab Research: Mnova MSChrom - Isotope Cluster Prediction for Elemental Composition Verification."/></p>
<h3><strong>Mnova MSChrom Market and Users</strong></h3>
<ul>
<li>Teaching MS and Chromatography to chemistry departments</li>
<li>Research in organic, medicinal and environmental chemistry</li>
<li>Quality control in chemical and pharmaceutical companies</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_users_507a260da1.jpg" alt="Mestrelab Research: Mnova MSChrom users."/></p>
<h3><strong>Frequently Asked Questions</strong></h3>
<h5><strong>How can I know if my data is compatible with Mnova?</strong></h5>
<p><em>Mnova MS supports most of the different MSChrom data formats. You can check it on the MSChrom supported format table <a href="http://www2.mestrelab.com/l/271522/2024-04-10/3p2gs6"><strong>here</strong></a>. Please let us know if your MSChrom data format is not in the list.</em></p>
<h5><strong>How much does the MSChrom module cost?</strong></h5>
<p><em>You can find the cost of this module in our online store. You can also check out for any combo option if you have or you need Mnova NMR. For any questions about pricing you can always contact us directly at <strong>sales@mestrelab.com</strong></em></p>
<h5><strong>I have Mnova NMR and I am wondering if I could add my MS data to my NMR reports.</strong></h5>
<p><em>Yes. You can open NMR and MS data in the same document, and cut/paste the MSChrom display to the same page of NMR data if needed. Or you can create a display template to automatically format the reports.</em></p>
<h5><strong>Can I use my MSChrom data for verification purposes?</strong></h5>
<p><em>Yes. Run Molecule Match in Mnova MSChrom to verify the elemental composition automatically, or run Mnova Verify to verify a proposed structure against your MS data (Mnova Verify needs a separate license).</em></p>
<h5><strong>Can I use it to process my High Resolution MSChrom data?</strong></h5>
<p><em>Yes. Both high resolution and low resolution MS data can be used by Mnova MSChrom. Just make sure you set the proper mass tolerance parameters when you do Molecular Match.</em></p>
<h5><strong>Can I try Mnova MSChrom?</strong></h5>
<p><em>Yes, you can download a 45-day trial license of any of our products. The Mnova MSChrom module is included within the main Mnova installer. Download Mnova and try it now!</em></p>
<h3><strong>Case Studies</strong></h3>
<h4><strong>Automated analysis and reporting LC/MS and NMR together for compound registration – A case study</strong></h4>
<p>A pharma company does quality control of their compounds using both NMR and LC/MS before registration, and generates the analysis reports in their own format. Based on their requirement, we developed a Mnova script (R_NMR_MS.qs) that does all of this automatically.</p>
<blockquote>
<p><a href="http://www2.mestrelab.com/l/271522/2024-04-10/3p2gs9"><strong>read more</strong></a></p>
</blockquote>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mnova_MS_Chrom_Automated_analysis_and_reporting_LC_MS_and_NMR_together_for_compound_registration_A_case_study_8003aab1ff.jpg" alt="Mestrelab Research: Mnova MSChrom - Automated analysis and reporting LC-MS and NMR together for compound registration – A case study."/></p>


Mestrelab Mnova Gears – Chrom Best Method software

Chrom Best Method is a vendor agnostic tool that can seamlessly screen and compare several chromatographic methods, then suggest the one that is more likely to yield a pure compound.

<h3><strong>Automated solution for selection of the optimal separation method</strong></h3>
<p>Data processing and comparison between different chromatographic methods can quickly form a bottleneck when large amounts of data is generated, particularly when multiple different instruments are involved.</p>
<p><strong>Chrom Best Method</strong> is a vendor-agnostic tool that can seamlessly <strong>screen and compare several chromatographic methods</strong>, then suggest the one that is more likely to yield a pure compound. Chrom Best Method <strong>automates LC-MS data processing</strong>, <strong>target and impurity identification</strong>, <strong>method scoring</strong>, and <strong>report generation</strong>, to provide quick, smart, and robust answers, whilst still allowing for full review and overriding of results to accommodate users’ needs.</p>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mestrelab_Mnova_Gears_Chrom_Best_Method_software_Find_the_best_separation_conditions_for_your_compounds_with_Chrom_Best_Method_7d0d3f9805.jpg" alt="Mestrelab Research: Save time and money – find the best separation conditions for your compounds with Chrom Best Method!"/></p>
<blockquote>
<h3><a href="http://www2.mestrelab.com/l/271522/2024-03-25/3nwskj"><strong>Visit MestreLab Research Mnova Gears – Chrom Best Method product page to learn more!</strong></a></h3>
</blockquote>
<h3><strong>Chrom Best Method Benefits</strong></h3>
<ul>
<li>Effective, <strong>vendor-neutral analysis and comparison of your LC-MS data from different instruments</strong> in one software package.</li>
<li>Seamless <strong>evaluation of several methods</strong> for many targets in a single run, which accommodates <strong>HT experimentation</strong>.</li>
<li>Meaningful <strong>method scores</strong> based on your criteria, preferences, and operational requirements.</li>
<li>Substantial <strong>reduction in the time spent</strong> on manual analysis and creation of reports.</li>
<li>Effective <strong>result visualization and interpretation</strong>, enabling quick and confident decision making.</li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mestrelab_Mnova_Gears_Chrom_Best_Method_software_2_8cff8a724b.jpg" alt="Mestrelab Research: Mestrelab Mnova Gears – Chrom Best Method software"/></p>
<h3><strong>Chrom Best Method Features</strong></h3>
<ul>
<li><strong>Automated data preparation, analysis, and reporting of results</strong></li>
<li>Comprehensive <strong>method scoring</strong> that generates meaningful results</li>
<li>Powerful target <strong>peak assignment options</strong> and <strong>detection of impurities</strong></li>
<li><strong>Multiple ways to provide target information</strong> (using a structure, dataset file name, mapping file, or parameters)</li>
<li><strong>Flexible ion matching and analysis options</strong> that fit multiple-use cases</li>
<li>Optimized <strong>algorithm for chiral screening</strong></li>
<li>Possibility to <strong>screen methods on different targets in a single run</strong></li>
<li><strong>Manual review</strong> by exception of scoring and <strong>ability to override results</strong></li>
</ul>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mestrelab_Mnova_Gears_Chrom_Best_Method_software_ccc0c0e0ad.jpg" alt="Mestrelab Research: Mestrelab Mnova Gears – Chrom Best Method software."/></p>
<h3><strong>Purification Workflow</strong></h3>
<h4><strong>More Automation</strong></h4>
<p>Looking for an enterprise-level solution for improving your purification and data management procedures? Check the <a href="http://www2.mestrelab.com/l/271522/2024-03-25/3nwskm"><strong>Fraction Analysis</strong></a> and <a href="http://www2.mestrelab.com/l/271522/2024-03-25/3nwskq"><strong>Quality Control</strong></a> bricks that also run in full automation with Mgears. You have the complete flexibility to combine and adapt these solutions to your standard procedures to reap even more benefits to your organization.</p>
<p><a href="http://www2.mestrelab.com/l/271522/2024-04-10/3p2gsh"><strong>Contact us</strong></a> for more information.</p>
<p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Research_Mestrelab_Mnova_Gears_Chrom_Best_Method_software_4_f25f63daa7.jpg" alt="Mestrelab Research: Mestrelab Mnova Gears – Chrom Best Method software"/></p>
<h3><strong>Markets</strong></h3>
<p>Academic, Government &amp; Industrial</p>
<h4><strong>Who should be using Chrom Best Method?</strong></h4>
<p>Organic chemists, analysts, QC experts, and researchers using quantitative chromatographic methods for quality control, concentration/purity determination, or monitoring/optimization of reactions in one of the following markets and applications:</p>
<ul>
<li><p>Pharmaceutical / Drug development industry</p>
</li>
<li><p>Food &amp; Beverage industries</p>
</li>
<li><p>Personal care and Cosmetics</p>
</li>
<li><p>Fine chemical synthesis industries</p>
</li>
<li><p>Polymer industries</p>
</li>
<li><p>Academic research laboratories</p>
</li>
<li><p>Contract Research Organizations (CROs) offering purification services</p>
</li>
<li><p>Compound purification for subsequent use in studies or commercialization</p>
</li>
<li><p>Isolation of unknown impurities in finished products, natural products, or in the environment for structural disclosure, study, etc.</p>
</li>
<li><p>Chiral separation to remove unwanted enantiomers obtained during organic synthesis</p>
</li>
</ul>


Products focused on GC/MSD distributed by SciY/Mestrelab Research - page 1

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