<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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Watrex SCI-AQUA ULTRAPUR Water Purification System

WATREX ULTRAPURE is dedicated to preparaton of ultrapure water for analytical, biochemical and other laboratories.

<p><strong>WATREX ULTRAPURE is dedicated to preparaton of ultrapure water for analytical, biochemical and other laboratories where the water with specific conductivity values below 0.1 µS/cm and a TOC value of less than 50 ppb is required.</strong></p><p>The device is <strong>fed with pressurized pre-treated water</strong>, preferably with conductivity values below 15 µS/cm (e.g. water treated by reverse osmosis).</p><p><a target="_blank" rel="noopener noreferrer" href="https://watrex.com/obchod/water-purification/ultra-pure-water/ultrapur-laboratory-unit-for-ultra-pure-water-preparation-2/?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_produkty"><strong>Watrex ULTRAPUR</strong></a> is supplied with a <strong>digital flow conductometer</strong> that allows monitoring the proper functioning of the device and the need to replace exhausted filter cartridges.</p><p>The water treated by ULTRAPURE system is <strong>suitable for HPLC, AA, ICP</strong> and other demanding analyses.</p><p><strong>The maintenance of the device is very simple</strong> and consists only in replacing the filter inserts after they are exhausted.</p><p><span style="font-size:18px;"><strong>Price: 923</strong><bdi><span class="wmc-cache-pid woocommerce-Price-amount amount" data-wmc_product_id="24487"><strong>&nbsp;</strong></span><span class="wmc-cache-pid woocommerce-Price-amount amount woocommerce-Price-currencySymbol" data-wmc_product_id="24487"><strong>€</strong></span></bdi><span class="wmc-cache-pid" data-wmc_product_id="24487"><strong> </strong></span><small class="woocommerce-price-suffix"><span class="wmc-cache-pid" data-wmc_product_id="24487"><strong>ex. VAT</strong></span></small></span></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Watrex_Water_purification_systems_8810a2c48a.jpg" alt="Watrex: Water purification systems" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Watrex_Water_purification_systems_8810a2c48a.jpg 245w," sizes="100vw" width="2286" height="1130"></p><p>Basic requirements for laboratory operations include the easy availability of <strong>pure laboratory water</strong> in the necessary <strong>quantity and quality</strong>. Distillation, a popular technique for producing purified water in the past, has virtually completely supplanted by less energy-intensive and operationally dependable alternatives today. <strong>Reverse osmosis</strong> is the foundation of the majority of contemporary systems for <strong>producing purified water</strong>; in reality, this principle is supplemented with <strong>adsorption</strong>, <strong>ion exchange</strong>, <strong>filtration</strong>, <strong>ultrafiltration</strong>, and other physical-chemical techniques.</p>

Watrex xTrovert FLEX-O automation SPE sample preparation system

FLEX-O robotic system enabling automation sample preparation on solid phase using 96-titre plates.

<p><strong>FLEX-O robotic system enabling automation sample preparation on solid phase using 96-titre plates. Although there are solutions for automatic SPE on classic column formats, robotic system for automation in 96-well SPE plates is not currently on the market.</strong></p><p>In addition to <strong>the 8-channel pipetting head</strong>, the robot is equipped with <strong>a gripper</strong> and <strong>a filling dispenser</strong>, which applies wash solutions to the SPE positions on the plate. Instead of filtering using classic vacuum pump, which is used for manual SPE on columns or 96plates, the <a target="_blank" rel="noopener noreferrer" href="https://watrex.com/obchod/laboratory-automation/xtrovert-flex-o/?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_produkty"><strong>xTrovert FLEX-O</strong></a> system uses the so-called <strong>positive pressure technology</strong> when it is the reagent is pushed through the SPE membrane with a multi-channel pressure attachment. That’s it ensuring <strong>flow uniformity and reproducibility</strong> between individual samples on the plate.</p><p>The robot is capable of <strong>processing up to 4 x 96-well sample plates</strong> (384 of total samples) using a protocol with <strong>up to 8 different washing and extraction reagents</strong>.The system is <strong>compatible with the Waters OligoWorks™ SPE Macroplate</strong> (96-well), <strong>Waters Oasis™ PRiME HLB</strong>, <strong>Macherey-Nagel™ SPE MULTI 96-Monoblock CHROMABOND™</strong> and other 96-plate format SPE systems.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Watrex_x_Trovert_FLEX_O_automation_SPE_sample_preparation_system_ec3768960e.jpg" alt="Watrex xTrovert FLEX-O automation SPE sample preparation system.jpg" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Watrex_x_Trovert_FLEX_O_automation_SPE_sample_preparation_system_ec3768960e.jpg 208w," sizes="100vw" width="1433" height="1075"></p><p>If necessary, the <strong>user can make modifications to the log</strong> using a simple scripting language and subsequent wireless upload to the device. Userthe interface for controlling the system is based on the integrated computer Raspberry Pi ® s 800×480 RGB LCD multi-touch touch screen and the possibility of remote wifi accessfrom an external device (e.g. mobile phone or tablet).</p><h4>Application</h4><ul><li><strong>Purification of oligonucleotide synthesis products</strong></li><li><strong>Organic Synthesis</strong></li><li><strong>Environmental Analysis</strong></li><li><strong>Medical diagnostics</strong></li><li><strong>Molecular biology and biochemistry</strong></li></ul><p>The entire system was designed and developed by Watrex Praha and is <strong>manufactured in the Czech Republic</strong> and promises a shift in the performance and efficiency of laboratory processes worldwide!</p>

LECO Paradigm Flow Modulator and Shift Flow Splitter

Paradigm RFF Flow Modulator with Shift Flow Splitter boosts GC×GC peak capacity while maintaining constant MS/FID split ratios, enabling accurate, repeatable quantitation across full volatility ranges.

<p><strong>The Paradigm Flow Modulator with Reverse Fill-Flush (RFF) technology dramatically expands chromatographic peak capacity across the full volatility range while preserving quantitative accuracy. The RFF modulator fills a fixed-volume sample loop with effluent from the first-dimension column and then rapidly flushes it onto an orthogonal second-dimension stationary phase. This true comprehensive GC×GC transfer ensures excellent repeatability, robust quantitation, and high-quality separations for complex samples.</strong></p><h3><strong>Key features</strong></h3><ul><li><strong>Reverse Fill-Flush (RFF) modulation</strong> for true comprehensive GC×GC with complete analyte transfer</li><li><strong>Novel chromatography splitter</strong> with two channels of pressure assistance</li><li><strong>Designed for high flows</strong> required for RFF modulation (≈20 mL/min)</li><li><strong>Constant MS/FID split ratio</strong> maintained throughout the entire run, including oven temperature ramps</li></ul><h3><strong>ChromaTOF makes modulation simple</strong></h3><p>Paradigm eliminates complex offline flow calculations. Integrated <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/41"><strong>ChromaTOF® software</strong></a> automatically performs all required calculations via a straightforward interface. The resulting methods are optimized to deliver complete analyte transfer, excellent peak shapes, and high chromatographic resolution—without manual trial-and-error.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Chromatof_flow_calculation_6b8ca60f99.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter: ChromaTOF Software identifies method calculation improvements for RFF modulation" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Chromatof_flow_calculation_6b8ca60f99.jpg 245w," sizes="100vw" width="670" height="426"></p><h3><strong>A shift forward in chromatographic analyses</strong></h3><p>The <strong>Shift Flow Splitter</strong> introduces a novel splitting mechanism that maintains a constant split ratio between MS and FID across the full GC oven program. Compared to traditional splitters, Shift delivers superior quantitative accuracy with minimal internal standardization, greatly simplifying compound-level and group-type quantitation in GC and GC×GC workflows.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_LECO_Paradigm_G_Cx_GC_prutokovy_modulator_a_Shift_splitter_5_245c7c2fde.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter:   Close-up on the Shift Flow Splitter installed in a GC oven" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_LECO_Paradigm_G_Cx_GC_prutokovy_modulator_a_Shift_splitter_5_245c7c2fde.jpg 245w," sizes="100vw" width="2925" height="825"></p><h3><strong>Software-optimized detector performance</strong></h3><p>ChromaTOF automatically balances and optimizes the flow directed to TOFMS and FID, ensuring proper peak shapes and matched sensitivity for reliable qualitative and quantitative results.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/LECO_Optimize_flow_e51d505415.jpg" alt="LECO Paradigm Flow Modulator and Shift Flow Splitter:   ChromaTOF Software automatically optimizes flow rates" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_LECO_Optimize_flow_e51d505415.jpg 207w," sizes="100vw" width="808" height="608"></p>

Watrex SYRINGE FILTERS

Syringe filters (filters for syringes) are a universal tool that ensures sample purity and prevents contamination of analytical instruments.

<p><strong>Syringe filters (filters for syringes) are a universal tool that ensures sample purity and prevents contamination of analytical instruments. They are single-use filters used for precise filtration of liquids before their application or analysis.</strong></p><p><strong>Pore Size: </strong>Filters come in various pore sizes, ranging from 0.2 μm to 5 μm, depending on the required level of filtration. Smaller pores (e.g., 0.22 μm) are often used for sterilizing solutions, as they capture bacteria and other microorganisms.</p><p>We offer syringe filters in the following sizes: <strong>4 mm, 13 mm, 25 mm, and 30 mm</strong>, all available with pore sizes of <strong>0.22 μm and 0.45 μm</strong>.</p><p><strong>Filter Material:</strong> Syringe filters are made from different materials that are compatible with various sample types. It is important to select the correct filter material based on the chemical composition of the sample. We offer syringe filters made from the following materials:</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Watrex_Watrex_SYRINGE_FILTRY_b6ffda00e2.jpg" alt="Watrex: Watrex SYRINGE FILTERS" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Watrex_Watrex_SYRINGE_FILTRY_b6ffda00e2.jpg 245w," sizes="100vw" width="1808" height="1017"></p><h4><strong>Nylon</strong></h4><ul><li>Suitable for <strong>aqueous solutions</strong> and most <strong>organic solvents</strong>.</li><li>It has strong <strong>mechanical stability</strong> and excellent chemical compatibility with <strong>esters, bases, phenols, and alcohols.</strong></li></ul><h4><strong>PTFE (Polytetrafluoroethylene)</strong></h4><ul><li>Chemically resistant to most <strong>organic solvents</strong>.</li><li>It has very broad chemical and thermal compatibility.</li><li>PTFE filters are recommended for <strong>strong acids and bases</strong> and are excellent for filtration and degassing chromatography.</li></ul><h4><strong>PVDF (Polyvinylidene fluoride)</strong></h4><ul><li>Suitable for <strong>biological samples</strong>.</li><li>It has good <strong>chemical resistance</strong> and low UV absorption.</li><li>Commonly used for filtering all water-based samples and most solvents.</li></ul><h4><strong>PES (Polyester)</strong></h4><ul><li>Ideal for <strong>water-based samples</strong>, especially <strong>biological ones</strong>, with a fast and high flow rate.</li></ul><h4><strong>MCE (Mixed Cellulose Esters)</strong></h4><ul><li>Ideal for <strong>aqueous samples</strong>, <strong>tissue cultures</strong>, and <strong>sensitive biological samples</strong>.</li><li>It has lower chemical resistance, excellent water flow, and a better cutoff effect.</li></ul><h4><strong>PP (Polypropylene)</strong></h4><ul><li>Ideal for filtering all water-based samples and most solvents.</li><li>Used for general <strong>filtration of biological samples</strong>, <strong>solvents</strong>, <strong>deionized water</strong>, and reducing biological load.</li><li>It has good thermal compatibility.</li></ul><h5><strong>Examples of Use:</strong></h5><ol><li><strong>Sterilization of solutions: </strong>Filtration can remove bacteria and other microorganisms from solutions.</li><li><strong>Sample purification: </strong>Samples are filtered before analysis to remove solid particles that could contaminate analytical instruments or affect analysis results.</li><li><strong>Preparation for chromatography:</strong> Filtration before entering devices like HPLC (High-Performance Liquid Chromatography) to ensure sample purity.</li></ol><p><strong>You can also visit the full range of syringe filters on the </strong><a target="_blank" rel="noopener noreferrer" href="https://watrex.com/?s=syringe+filters&amp;post_type=product&amp;dgwt_wcas=1?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_produkty"><strong>Watrex website</strong></a><strong>.</strong></p>

Watrex VICI Consumables for HPLC/GC

As an authorized distributor of VICI, we provide a wide range of high-quality chromatography consumables that meet the most demanding requirements for precision and reliability.

<p><strong>As an authorized distributor of VICI, we provide a wide range of high-quality chromatography consumables that meet the most demanding requirements for precision and reliability.</strong></p><p>Our offer includes <strong>injection valves, adapters, tubing, filters, columns</strong> and other products that optimize the performance of your HPLC systems. Thanks to our close cooperation with partners, we guarantee the latest technology and expert advice.</p><p>Explore our range using the <strong>catalogs from</strong><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Watrex_VICI_V_ddafed74a8.pdf"><strong> VICI Valco</strong></a><strong> and </strong><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Watrex_VICI_J_c72f706329.pdf"><strong>VICI Jour</strong></a> and do not hesitate to contact us for a non-binding quote at watrex@watrex.com or visit our website <a target="_blank" rel="noopener noreferrer" href="https://watrex.com/cs/uvod/?utm_source=labrulez">www.watrex.com</a>.</p><h3>VICI Valco Instuments</h3><p>For over 50 years, VICI Valco Instruments Co. Inc. has been the leading designer and manufacturer of standard and custom valves and fittings for precision analytical, biomedical, and biocompatible instrumentation.</p><h4>The offer includes, for example:</h4><ul><li><strong>Injectors and valves</strong></li><li><strong>Fittings</strong></li><li><strong>Detectors</strong></li><li><strong>Valve actuation and accessories</strong></li></ul><p>Vici Valco product line also includes a wide range of related products such as pneumatic and electric actuators, tubing and sampling loops, heated enclosures, valve sequence and temperature controllers, gas purifiers, GC detectors, and digital interfaces.</p><h3>VICI Jour</h3><p>VICI Jour offer the complete Jour line of accessories and consumables for fluid transfer in HPLC and LC.</p><h4>The offer includes, for example:</h4><ul><li><strong>Tubing (PEEK, F-polymeric, stainless steel)</strong></li><li><strong>Fittings (high pressure and low pressure)</strong></li><li><strong>Filters (high pressure and low pressure) and frits</strong></li><li><strong>Safety products</strong></li><li><strong>PEEK columns and guard columns</strong></li><li><strong>Tools and LC accessories</strong></li></ul><p>Jour products include a complete line of tubing and capillaries in a wide variety of diameters and materials, high and low pressure fingertight fittings and connection accessories, column hardware, high and low pressure filters, cutters and other tools, solvent saver, safey caps, waste caps, backpressure regulators, and much more.</p>

Mestrelab Research Chrom SST (System Suitability Testing) software

Chrom SST is a tool designed to automate System Suitability Testing data processing and analysis. It compares SST data to predefined specifications and provides actionable insights on instrument performance.

<p><strong>Automating data analysis for System Suitability Testing</strong></p><p><strong>Chrom SST is a vendor-agnostic tool </strong>designed to <strong>automate System Suitability Testing (SST) data processing and analysis</strong>. It compares SST data to predefined specifications and provides actionable insights on instrument performance.</p><h4><strong>Benefits</strong></h4><ul><li><strong>Integrates with various instruments</strong>, offering flexibility and scalability</li><li>Centralizes data for easy dashboarding enabling <strong>performance monitoring and preventive maintenance</strong></li><li>Enhances lab productivity and instrument uptime by allowing <strong>scheduling and automation of analyses</strong></li><li>Provides accurate and easy-to-interpret results, <strong>reducing manual effort and errors</strong></li></ul><h4><strong>Features</strong></h4><h5><strong>Simplified and Intuitive UI</strong></h5><p><strong>Chrom SST</strong> features a user-friendly interface designed to streamline the setup and execution of analyses, making it accessible even to non-experts. The intuitive layout ensures users can quickly perform essential tasks without requiring extensive training.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_2_537f61b491.jpg" alt="Mestrelab Research Chrom SST: Simplified and Intuitive UI" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_2_537f61b491.jpg 245w," sizes="100vw" width="736" height="427"></p><h5><strong>Automated Evaluation and Customization</strong></h5><p>The tool a<strong>utomates the evaluation of system suitability data</strong> against predefined specifications, delivering precise pass/fail outcomes. With robust customization options, users can tailor methods to their specific requirements and reuse them effortlessly, enabling faster setups and ensuring consistent, reliable results.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_097ef6b122.jpg" alt="Mestrelab Research Chrom SST: Automated Evaluation and Customization" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_097ef6b122.jpg 245w," sizes="100vw" width="736" height="427"></p><h5><strong>Enhanced Data Presentation</strong></h5><p><strong>Chrom SST</strong> includes a results dashboard and a comprehensive error-handling system. Clear messages and visual flags help identify and resolve system failures promptly, ensuring dependable and accurate performance assessments.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_3_9cdf4f6d7b.jpg" alt="Mestrelab Research Chrom SST: Enhanced Data Presentation" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_3_9cdf4f6d7b.jpg 245w," sizes="100vw" width="736" height="427"></p><h5><strong>Versatile Output Formats</strong></h5><p>Chrom SST supports <strong>various output formats</strong>, including Mnova files, PDFs, CSVs, and JSON, ensuring seamless interoperability with third-party tools. This versatility enables data centralization, visualization, and advanced analytics, empowering labs to fully leverage their data’s potentia.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_4_8c7bae67dd.jpg" alt="Mestrelab Research Chrom SST: Versatile Output Formats" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Mestrelab_Chrom_SST_Automating_data_analysis_for_System_Suitability_Testing_4_8c7bae67dd.jpg 245w," sizes="100vw" width="736" height="427"></p>

DataApex Clarity DHA (Detailed Hydrocarbon Analysis) Extension

The DHA Extension is a software module for DHA calculations and reporting based on supported standards.

<div><div id=""><div><div><div><div><strong>Extension for Detailed Hydrocarbon Analysis. It allows the determination of individual components in spark ignition engine fuels.</strong></div></div></div></div></div></div><div><div id=""><div><div><div><div><div><p>DHA Extension brings you the ability to calculate the properties of the samples directly in the chromatography software with the complete workflow of <strong>data acquisition</strong>, <strong>peak calibration</strong>, <strong>DHA calculations</strong> based on supported norms and reporting. These methods are often referred to as <strong>PONA</strong>, <strong>PIONA</strong>, <strong>O-PON</strong>A, etc.</p><p>Calculations in the <strong>DHA Extension</strong> currently support the <strong>ASTM D-6730</strong> standard and methods developed by <strong>Dani Instruments SA</strong>.</p></div></div></div></div></div></div></div><p><img style="aspect-ratio:1151/879;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_2_edfc9ba1f3.jpg" alt="DataApex Clarity DHA (Detailed Hydrocarbon Analysis) Extension" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_2_edfc9ba1f3.jpg 204w," sizes="100vw" width="1151" height="879"></p><p>You can create an <strong>additional custom method</strong> based on your own laboratory condititions or we can implement a standard method as part of the DHA extension at your request.</p><p>If you request to implement another norm in the DHA Extension, please contact us at <a href="mailto:support@dataapex.com">support@dataapex.com</a>.</p><p>The DHA Extension is optional and it can only be used together with <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/999"><strong>Clarity</strong></a>.</p><p>Note that for more complex DHA calculations, Clarity DHA Extension should be complemented by specialized software (e.g. Dragon II DHA© - see the <a target="_blank" rel="noopener noreferrer" href="https://www.dataapex.com/downloads/26175/view">D151 datasheet</a> for more details).</p><p><strong>The DHA Extension is an optional fully integrated addition to </strong><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/999"><strong>Clarity software</strong></a><strong>. It can be ordered as part of a new installation or as an extension to an existing one. There are two variants to this extension:</strong></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_bc1e53cf67.jpg" alt="DataApex Clarity DHA (Detailed Hydrocarbon Analysis) Extension" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_bc1e53cf67.jpg 211w," sizes="100vw" width="1223" height="906"></p><h5><strong>p/n A33</strong></h5><ul><li>includes general ASTM-D6730 standard method and the possibility to create custom method.</li></ul><h5><strong>p/n A331</strong></h5><ul><li>includes additional methods developed by DANI Instruments S.p.A</li></ul><h3 data-start="49" data-end="78"><strong data-start="53" data-end="76">Norms specification</strong></h3><h4 data-start="80" data-end="102"><strong data-start="85" data-end="100">ASTM D-6730</strong></h4><ul data-start="103" data-end="302"><li data-start="103" data-end="127">Included in p/n A33.</li><li data-start="128" data-end="302">Standard Test Method for Determination of Individual Components in Spark Ignition Engine Fuels by 100-Metre Capillary (with Precolumn) High-Resolution Gas Chromatography.</li></ul><h4 data-start="304" data-end="328"><strong data-start="309" data-end="326">Custom Method</strong></h4><ul data-start="329" data-end="441"><li data-start="329" data-end="353">Included in p/n A33.</li><li data-start="354" data-end="441">Allows you to create a custom method which meets the conditions in your laboratory.</li></ul><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_3_f5e659a432.jpg" alt="DataApex Clarity DHA (Detailed Hydrocarbon Analysis) Extension" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_3_f5e659a432.jpg 245w," sizes="100vw" width="1233" height="756"></p><h4><strong data-start="452" data-end="475">ASTM D-6730 by DANI</strong></h4><ul data-start="478" data-end="578"><li data-start="478" data-end="535">Method by Dani Instruments SA with cryogenic cooling.</li><li data-start="536" data-end="578">Available only at Dani Instruments SA.</li></ul><h4 data-start="580" data-end="619"><strong data-start="585" data-end="617">ASTM D 2421-02 and D 2598-02</strong></h4><ul data-start="620" data-end="720"><li data-start="620" data-end="677">Method by Dani Instruments SA with cryogenic cooling.</li><li data-start="678" data-end="720">Available only at Dani Instruments SA.</li></ul><h4><strong data-start="731" data-end="758">Extension specification</strong></h4><ul data-start="761" data-end="911"><li data-start="761" data-end="782"><strong data-start="763" data-end="776">Part No.:</strong> A33</li><li data-start="783" data-end="911"><strong data-start="785" data-end="806">Related products:</strong><ul data-start="811" data-end="911"><li data-start="811" data-end="832"><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/999">Clarity</a> (p/n C50)</li><li data-start="835" data-end="864"><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/1000">Clarity Offline</a> (p/n C59)</li><li data-start="867" data-end="911">GC or AS Control module (p/n A23 or A26)</li></ul></li></ul><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_2_d15379bcdf.jpg" alt="DataApex Clarity DHA - Detailed Hydrocarbon Analysis Extension" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Data_Apex_Clarity_DHA_Detailed_Hydrocarbon_Analysis_Extension_2_d15379bcdf.jpg 245w," sizes="100vw" width="1995" height="1182"></p>

Phenomenex Zebron PLUS GC Inlet Liners

GC liners Zebron PLUS with unique deactivation ensure high inertness for trace and active compound analysis.

<p class="cke-user_style-important"><strong>Protect and Increase the Lifetime of Your GC Column</strong></p><h4><strong>Why Use Pre-Packed Liners?</strong></h4><p>Though the upfront cost of self-packing your liner may seem attractive, the time and headaches caused by resulting tailing or irreproducible peaks can be sizeable! Self-packed wool fibers commonly break during installation and any existing deactivation on the liner can also be scratched or damaged. Pre-packed Zebron PLUS liners undergo the deactivation process with the quartz wool already in place, which ensures that any active sites that form during packing are not exposed.</p><h4><strong>Deactivation Protects Your Samples</strong></h4><h5><strong>See the difference: Zebron PLUS vs. Traditional Deactivation</strong></h5><p>Zebron PLUS GC inlet liners undergo a unique deactivation process, resulting in a remarkably inert pathway that prevents sample adsorption and degradation for active compounds.</p><p><strong>A: Zebron PLUS Deactivation</strong></p><p>Every batch of Zebron PLUS liners is manufactured with a thick layer of vapor-deposited deactivation for the highest inertness. They are then tested for activity using both EPA Methods 8081 and 8270 to ensure the highest level of sample protection possible.</p><p><strong>B: Traditional Deactivation</strong></p><p>Traditionally, liners have only been passivated with thin deactivation layers – and sometimes have not at all – putting your analytes at risk of adsorption or degradation!</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Zebron_PLUS_vs_Traditional_Deactivation_5c8ce20af6.jpg" alt="Phenomenex: Zebron PLUS vs. Traditional Deactivation" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Zebron_PLUS_vs_Traditional_Deactivation_5c8ce20af6.jpg 245w," sizes="100vw" width="909" height="567"><br>&nbsp;</p><h4><strong>Easy, Touch free Installation</strong></h4><ul><li>Remarkably inert GC inlet liners for superior sample protection</li><li>Easy to install, touchless packaging allows you to protect yourself from cuts or breakage</li><li>Eliminates contamination that may occur during the installation process</li></ul><p><strong>A: Pre-installed o-ring saves steps</strong></p><p><strong>B: Touchless installation prevents contamination</strong></p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Easy_Touch_free_Installation_of_Zebron_GC_Inlet_Liner_dd54ebc577.jpg" alt="Phenomenex: Easy, Touch free Installation of Zebron GC Inlet Liner" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Easy_Touch_free_Installation_of_Zebron_GC_Inlet_Liner_dd54ebc577.jpg 245w," sizes="100vw" width="907" height="573"></p><h4><strong>Liner Geometry Improves Performance</strong></h4><p>The geometry of a liner refers to the type and shape of a liner. Each geometry addresses a particular sample or injection type. use the chart below to determine the best geometry for your sample.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Liner_Geometry_Improves_Performance_9bd57c3c81.jpg" alt="Phenomenex: Liner Geometry Improves Performance" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Liner_Geometry_Improves_Performance_9bd57c3c81.jpg 245w," sizes="100vw" width="1391" height="362"></p><h3><strong>Choose Your Liner</strong></h3><h4><strong data-start="74" data-end="123">For Agilent® or Thermo Scientific® GC Systems</strong></h4><ul><li><strong>Direct Connect</strong> - Trace analysis, Splitless injections (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A50-01, AG2-0A50-05, AG2-0A50-25 &nbsp;</li></ul></li><li><strong>Single Taper</strong> - Pesticides (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A10-01, AG2-0A10-05, AG2-0A10-25 &nbsp;</li></ul></li><li><strong>Single Taper Z-Liner™</strong> - Semi-volatiles, Dirty samples (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A13-01, AG2-0A13-05, AG2-0A13-25 &nbsp;</li></ul></li><li><strong>Single Taper with Wool</strong> - Semi-volatiles (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A11-01, AG2-0A11-05, AG2-0A11-25 &nbsp;</li></ul></li><li><strong>Straight</strong> - Volatiles (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A00-01, AG2-0A00-05, AG2-0A00-25 &nbsp;</li></ul></li><li><strong>Straight Z-Liner™</strong> - Dirty samples, Volatiles, High initial oven temperatures (4 x 78.5 mm) &nbsp;<ul><li>Part Nos: AG2-0A03-01, AG2-0A03-05, AG2-0A03-25 &nbsp;</li></ul></li><li><strong>Straight Single Baffle</strong> - Semi-volatiles, Pesticides (1.8 x 71 mm) &nbsp;<ul><li>Part Nos: AG2-1F06-01, AG2-1F06-05, AG2-1F06-25 &nbsp;</li></ul></li></ul><h4><strong>For PerkinElmer® GC Systems</strong></h4><ul><li><strong>Single Taper </strong>- Pesticides (4 x 92 mm) &nbsp;<ul><li>Part Nos: AG2-2A10-01, AG2-2A10-05, AG2-2A10-25 &nbsp;</li></ul></li><li><strong>Single Taper Z-Liner™</strong> - Semi-volatiles, Dirty samples (4 x 92 mm) &nbsp;<ul><li>Part Nos: AG2-2A13-01, AG2-2A13-05, AG2-2A13-25 &nbsp;</li></ul></li><li><strong>Straight</strong> - Volatiles (4 x 92 mm) &nbsp;<ul><li>Part Nos: AG2-2A00-01, AG2-2A00-05, AG2-2A00-25 &nbsp;</li></ul></li><li><strong>Straight Z-Liner™</strong> - Volatiles, Dirty samples (2 x 86.2 mm) &nbsp;<ul><li>Part Nos: AG2-2E03-01, AG2-2E03-05, AG2-2E03-25 &nbsp;</li></ul></li><li><strong>Straight Z-Liner™</strong> - High initial oven temperatures (4 x 92 mm) &nbsp;<ul><li>Part Nos: AG2-2A03-01, AG2-2A03-05, AG2-2A03-25 &nbsp;</li></ul></li></ul><h4><strong>For Shimadzu® GC Systems</strong></h4><h5><strong>Shimadzu 17A GC Systems</strong></h5><ul><li><strong>Single Taper Z-Liner™</strong> - Pesticides (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-3B13-01, AG2-3B13-05, AG2-3B13-25 &nbsp;</li></ul></li><li><strong>Straight Z-Liner™</strong> - Volatiles, Dirty samples, High initial oven temperatures (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-3B03-01, AG2-3B03-05, AG2-3B03-25 &nbsp;</li></ul></li></ul><h5><strong>Shimadzu 2010 GC Systems&nbsp;</strong></h5><ul><li><strong>Single Taper</strong> - Pesticides (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-4B10-01, AG2-4B10-05, AG2-4B10-25 &nbsp;</li></ul></li><li><strong>Single Taper Z-Liner™</strong> - Semi-volatiles, Dirty samples (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-4B13-01, AG2-4B13-05, AG2-4B13-25 &nbsp;</li></ul></li><li><strong>Straight</strong> - Volatiles (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-4B00-01, AG2-4B00-05, AG2-4B00-25 &nbsp;</li></ul></li><li><strong>Straight Z-Liner™</strong> - Volatiles, Dirty samples, High initial oven temperatures (3.4 x 95 mm) &nbsp;<ul><li>Part Nos: AG2-4B03-01, AG2-4B03-05, AG2-4B03-25 &nbsp;</li></ul></li></ul>

Phenomenex Strata C18-E Solid Phase Extraction (SPE)

Strata C18-E is a silica-based end-capped C18 solid phase extraction (SPE) sorbent.

<p><strong>Strong Hydrophobic Retention Solid Phase Extraction (SPE)</strong></p><p>Strata C18-E is a <strong>silica-based</strong> <strong>end-capped C18</strong> solid phase extraction (SPE) sorbent that offers <strong>strong hydrophobic retention</strong> with negligible secondary polar interactions from active silanol groups. Strata C18-E can be best used for the <strong>extraction of hydrophobic</strong> or <strong>polar organic analytes</strong> from <strong>aqueous matrices</strong>. In addition, Strata SPE sorbents are manufactured with the highest purity and extensively tested to give clean extracts.</p><p>Strata C18-E is <strong>compatible</strong> with various formats, including <strong>C18 SPE cartridges</strong>. Our C18 SPE products are synonymous with quality, offering the highest purity and undergo rigorous testing to deliver consistently clean extracts for your analytical needs.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Strata_C18_E_748c192b52.webp" alt="Phenomenex: Strata-C18-E" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Strata_C18_E_748c192b52.webp 245w," sizes="100vw" width="500" height="150"></p><ul><li><strong>Surface Area (m²/g)</strong>: 500, m²/g</li><li><strong>Separation Mode:</strong> Reversed Phase</li><li><strong>Pore Size:</strong> 70, 100</li><li><strong>Particle Size:</strong> 20, 55</li><li><strong>Recommended Use: </strong>Extraction of hydrophobic molecules</li></ul><h4><strong>Starting Method</strong></h4><h5><strong>Strata Reversed Phase</strong></h5><ul><li><strong>Condition:</strong> 1 mL Methanol</li><li><strong>Equilibrate:</strong> 1 mL DI Water</li><li><strong>Load:</strong> Pretreated sample</li><li><strong>Wash</strong>: 1 mL 5% Methanol in DI Water, dry under vacuum for 2-5 min</li><li><strong>Elute:</strong> 1 mL Methanol</li></ul><p>Based on 100 mg/1 mL sorbent mass. The above is a convenient starting point for SPE method development, further optimization may be required to tailor the method for your specific extraction needs.</p>

Phenomenex Strata C18-U Solid Phase Extraction (SPE)

C18 sorbent with no end-capping, giving the phase moderate hydrophobic selectivity with slight polar selectivity due to the active silanol groups.

<p><strong>Moderate Hydrophobic Selectivity Solid Phase Extraction (SPE)</strong></p><p>C18 sorbent with <strong>no end-capping</strong>, giving the phase <strong>moderate hydrophobic selectivity</strong> with <strong>slight polar selectivity</strong> due to the active silanol groups.</p><p><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Strata_C18_U_f0c8e66506.webp" alt="Phenomenex: Strata C18-U SPE" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Strata_C18_U_f0c8e66506.webp 245w," sizes="100vw" width="500" height="150"></p><ul><li><strong>Surface Area (m²/g)</strong>: 500</li><li><strong>Separation Mode:</strong> Reversed Phase</li><li><strong>Pore Size:</strong> 70</li><li><strong>Particle Size:</strong> 55</li><li><strong>Recommended Use: </strong>Enhanced cleanup of hydrophobic compounds that contain hydroxy or amine functional groups</li></ul><h4><strong>Starting Method</strong></h4><h5><strong>Strata Reversed Phase</strong></h5><ul><li><strong>Condition:</strong> 1 mL Methanol</li><li><strong>Equilibrate:</strong> 1 mL DI Water</li><li><strong>Load:</strong> Pretreated sample</li><li><strong>Wash</strong>: 1 mL 5% Methanol in DI Water, dry under vacuum for 2-5 min</li><li><strong>Elute:</strong> 1 mL Methanol</li></ul><p>Based on 100 mg/1 mL sorbent mass. The above is a convenient starting point for SPE method development, further optimization may be required to tailor the method for your specific extraction needs.</p>

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