Scientists at IOCB Prague are uncovering new details of gene transcription. They have identified a previously unknown molecular mechanism by which the transcription of genetic information from deoxyribonucleic acid (DNA) into ribonucleic acid (RNA) can be initiated. The researchers focused on a specific class of molecules known as alarmones, which are found in cells across a wide range of organisms and whose levels often increase under conditions of cellular stress. The results were published in the prestigious scientific journal Nature Chemical Biology.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Hana Cahová, head of the Chemical Biology of Nucleic Acids research group." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Molecules of ribonucleic acid can carry a variety of chemical modifications at one end, known as caps. In eukaryotic organisms, including human cells, the best-known cap plays an important role in RNA stability and in regulating its subsequent fate. In recent years, however, it has become clear that alternative, non-canonical RNA caps also exist, although their formation and the mechanisms by which they are attached to RNA remain only partially understood. These include alarmone caps, formed by dinucleoside polyphosphate molecules, that protect cellular RNA at moments when the cell is under threat.In their study, <a target="_blank" rel="noopener noreferrer" href="https://cahova.group.uochb.cz/en">Dr. Hana Cahová</a> and colleagues examined bacterial RNA polymerase and investigated how this enzyme can initiate transcription using dinucleoside polyphosphates (NpNs) instead of the standard RNA building blocks. For the first time, the scientists described, at the atomic level, how RNA bearing an alarmone cap can be generated directly at the initiation of gene transcription. They also observed that NpNs bind through a different type of base pairing than is typically observed.The work was significantly shaped by Valentina Serianni from Hana Cahová’s team, who demonstrated the ability of dinucleoside polyphosphates to initiate gene transcription, and by Jana Škerlová, who focused on the structural analysis of RNA polymerase. Using cryogenic electron microscopy data, she showed how dinucleoside polyphosphate molecules bind within the active site of RNA polymerase – that is, the core of the enzyme where genetic information is transcribed. Together, their findings help to elucidate the processes that accompany the transcription of genetic information from DNA to RNA.Hana Cahová adds: “We’re describing something that truly occurs in cells and that we’re now able to observe directly at the level of individual molecules. This allows us to answer fundamental questions about cellular processes, such as how cells adapt to stress. RNA plays a central role in this, as it carries the cascade of information underlying any cellular response – for example, to threatening conditions caused by nutrient deprivation or temperature shock.”<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Tomáš Kouba, head of the Cryogenic Electron Microscopy core facility." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Cryogenic electron microscopy (cryo-EM) was central to the project. This part of the work was led by Dr. Tomáš Kouba, one of the authors of the study. “Cryogenic electron microscopy allows us to freeze biological molecules in a state very close to their natural form and then determine their three-dimensional structure. This makes it possible to look directly into the active centers of enzymes and observe their function down to the atomic level,” he explains.Last year, IOCB Prague opened a new <a target="_blank" rel="noopener noreferrer" href="https://cryoem.group.uochb.cz/en">cryo-EM center</a> that is unique within the Czech research environment. State-of-the-art cryogenic electron microscopes are housed in a specially designed building and enable the study of biological processes with exceptional structural precision.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg" alt="IOCB Prague: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: This work shows how NpnNs initiate bacterial transcription. Cryo-EM reveals how nucleobases pair with the template: one in canonical and one in reverse Watson–Crick mode, providing a structural basis for their function as non-canonical RNA caps." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg 245w," sizes="100vw" width="2000" height="1077"><blockquote><h4>The Original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41589-025-02134-5">Molecular insight into 5′ RNA capping with NpnNs by bacterial RNA polymerase</a></h4>Valentina M. Serianni, Jana Škerlová, Anna Knopp Dubánková, Anton Škríba, Hana Šváchová, Tereza Vučková, Anatolij Filimoněnko, Milan Fábry, Pavlína Řezáčová, Tomáš Kouba &amp; Hana Cahova&nbsp;Nat. Chem. Biol. 21 (2026)<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1038/s41589-025-02134-5">https://doi.org/10.1038/s41589-025-02134-5</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote><h4>Abstract</h4>RNA capped with dinucleoside polyphosphates has been discovered in bacteria and eukaryotes only recently. The likely mechanism of this specific capping involves direct incorporation of dinucleoside polyphosphates by RNA polymerase as noncanonical initiating nucleotides. However, how these compounds bind into the active site of RNA polymerase during transcription initiation is unknown. Here, we explored transcription initiation in vitro, using a series of DNA templates in combination with dinucleoside polyphosphates and model RNA polymerase from Thermus thermophilus. We observed that the transcription start site can vary on the basis of the compatibility of the specific template and dinucleoside polyphosphate. Cryo-electron microscopy structures of transcription initiation complexes with dinucleoside polyphosphates revealed that both nucleobase moieties can pair with the DNA template. The first encoded nucleotide pairs in a canonical Watson–Crick manner, whereas the second nucleobase pairs noncanonically in a reverse Watson–Crick manner. Our work provides a structural explanation of how dinucleoside polyphosphates initiate RNA transcription.</div></div>

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

In the week of February 9, the following webinars await you in the field of gas / solid phase and especially Raman, FTIR, GC and GC/MS.<blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars">👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</a></h4>👉 Search and filter in the largest global database with over 5 000 GC, LC, MS and spectroscopy webinars.</blockquote><div><div><div><div><div><div><h5>1. Thermo Fisher Scientific: Process Raman – A Reliable and Versatile Tool for Downstream Process Monitoring and Control for mAb Production</h5><ul><li>Tu, 10.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5808">Registration</a></li></ul>The presentation highlights how process Raman spectroscopy offers several advantages over traditional in-line UV-Vis analysis for process monitoring and metabolite production control in mAb manufacturing.<h5>2. Wasson-ECE Instrumentation: The Data Driven Plant – How AI Transforms Chemical Manufacturing</h5><ul><li>Tu, 10.2.2026 21:30 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5744">Registration</a></li></ul>Explore how artificial intelligence is applied to improve process efficiency, monitoring, and decision-making in modern chemical manufacturing.<h5>3. New Food Magazine: The Science of Next-Gen Ingredients – Fermentation, Formulation and Function</h5><ul><li>We, 11.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5720">Registration</a></li></ul>Discover how fermentation-driven innovation is transforming functional food ingredients, with analytical insights to optimize flavour, functionality, and product stability.</div></div></div></div></div></div>

Webinars LabRulezGCMS Week 07/2026

This study presents an analytical strategy combining QuEChERS extraction with low-temperature partitioning (LTP) for the determination of multiclass pesticide residues in cocoa beans by GC–MS. Extraction conditions were optimized using a fractional factorial design, resulting in a simple and efficient workflow suitable for complex cocoa matrices.The validated method showed satisfactory limits of detection and quantification, recoveries within 70–120%, and good overall performance. Application to cocoa samples from Brazil detected permethrin in several samples, demonstrating that the QuEChERS–LTP approach is an effective and reliable cleanup strategy for routine pesticide residue analysis in cocoa.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360">QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans</a></h4>Priscilla M. de Freitas Machado, Madson M. Nascimento, Paulo R. R. Mesquita, Manuela B. Nascimento, Lilian Lefol N. Guarieiro, Gisele O. da Rocha, Jailson B. de Andrade, Raildo M. de Jesus*ACS Omega 2025, 10, 51, 63464–63473<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsomega.5c10360">https://doi.org/10.1021/acsomega.5c10360</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.Cocoa is best known as the primary raw material for chocolate but is also processed into products such as cocoa butter, biscuits, cocoa honey, and cocoa powder. Cocoa powder is derived from roasted, pressed, and milled nibs, containing on average 20% (w/w) lipids on a dry basis and less than 9% moisture. <a href="javascript:void(0);">(3,4)</a>According to the Brazilian Health Regulatory Agency (ANVISA), pesticides such as atrazine, bifenthrin, cyproconazole, metalaxyl, tebuconazole, trifloxystrobin, and permethrin are approved for use in Brazil. <a href="javascript:void(0);">(13)</a> However, among these, only metalaxyl, trifloxystrobin, and tebuconazole are authorized by the European Union. <a href="javascript:void(0);">(14)</a> Thus, investigating these contaminants in cocoa samples is of utmost importance, as Brazil is one of the largest cocoa exporters, supplying cocoa commodities to South America, the United States, and the European Union. <a href="javascript:void(0);">(2)</a> Furthermore, Organochlorine pesticides, in particular, belong to the class of persistent organic pollutants (POPs). Although banned in many countries, they continue to be used in some developing nations because of their chemical stability, resistance to degradation, volatility, and high lipophilicity, which promote bioaccumulation and neurotoxicity. <a href="javascript:void(0);">(15)</a> Epidemiological evidence also associates their exposure with Parkinson’s disease, certain cancers, diabetes, and endometriosis. <a href="javascript:void(0);">(16)</a>Residues of pesticides in cocoa have been reported in various studies. <a href="javascript:void(0);">(17)</a> Analyzing pesticide residues in cocoa presents analytical challenges due to the matrix’s complexity, comprising high lipid content, fatty acids and esters, sugars, polyphenols, and caffeine. These components can interfere with extraction efficiency and contaminate analytical instrumentation. <a href="javascript:void(0);">(18)</a> Therefore, efficient sample preparation methods incorporating effective cleanup steps are essential for accurate residue determination.Several techniques have been employed for multiresidue pesticide analysis in cocoa. For instance, Idowu et al. <a href="javascript:void(0);">(19)</a> quantified 14 organochlorines using Soxhlet extraction and silica/Na2SO4 cleanup, with GC ECD detection. Okoffo et al. <a href="javascript:void(0);">(20)</a> determined 13 organophosphates and 9 pyrethroids employing SPE cartridges (Envi-carb/LC-NH2 and Bond Elute C18), acetonitrile extraction, and GC PFPD or GC ECD quantification. Yusiasih et al. <a href="javascript:void(0);">(21)</a> applied dispersive SPE with PSA, Florisil, and MgSO4 for pyrethroids, followed by GC ECD and GC–MS.Therefore, this study aimed to evaluate the effectiveness of a QuEChERS–LTP analytical procedure for the determination of multiclass pesticide residues in cocoa beans. The factors that affect the QuEChERS–LTP procedure efficiency were optimized. After validation, the procedure was employed to investigate the occurrence of 15 multiclass pesticides in cocoa samples.<h4>Experimental Section</h4><h5>Instrumental Apparatus</h5>Pesticide separation and identification were performed on a Shimadzu <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GC-MS-QP2010SE">GC-MS-QP2010SE</a> system (Kyoto, Japan) equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-20i">AOC-20i autosampler</a>. Separation was achieved using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-5MS">Agilent DB-5MS capillary column</a> (30 m × 0.25 mm × 0.25 μm) with a stationary phase of 5% phenyl/95% dimethylpolysiloxane. The instrumental conditions were based on Nascimento et al. <a href="javascript:void(0);">(49)</a> and they are summarized in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl4">Table 4</a>.For quantification, the base peak was used, while two additional ions were monitored for confirmation (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Table S2</a>) in accordance with SANTE guidelines. <a href="javascript:void(0);">(50)</a> A GC–MS/SIM chromatogram illustrating the separation of all target pesticides is presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig5">Figure 5</a>.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 5. Extracted ion chromatogram (EIC) in SIM mode of the target pesticides obtained from the injection of a mixed standard solution at 100 μg L–1. Analytes are listed in order of elution: [1] Molinate (6.18 min); [2] α-HCH (8.15 min); [3] atrazine-d5 (8.69 min); [4] atrazine (8.75 min); [5] diazinon (9.31 min); [6] disulfoton (9.67 min); [7] dimethachlor (10.60 min); [8] metalaxyl (11.25 min); [9] p,p′-DDE (15.82 min); [10] cyproconazole I (16.50 min); [11] cyproconazole II (16.56 min); [12] p,p′-DDD (17.29 min); [13] ethion (17.34 min); [14] trifloxystrobin (18.43 min); [15] tebuconazole (19.13 min); [16] bifenthrin (20.47 min); [17] permethrin I (23.92 min); [18] permethrin II (24.18 min)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg 245w," sizes="100vw" width="2080" height="835"><h5>Application of the Proposed Procedure to Real Samples</h5>In a 50 mL Falcon tube, 2.0 g of sample was weighed using an analytical balance (AUX320, Shimadzu, Kyoto, Japan). A total of 2.0 g of salt (NaCl and Na2SO4 in a 1:1 w/w ratio) was added, followed by an aliquot of the atrazine-d5 solution (surrogate standard) to yield a final concentration of 250 μg kg–1. A mixture of acetonitrile (8.0 mL) and ultrapure water (2.0 mL) was then added. The system was vortexed (K40-10208, Kasvi, São Paulo, Brazil) for 3.0 min at 2500 rpm and centrifuged (MPW-351R, MPW Med. Instruments, Warsaw, Poland) for 10.0 min at 15 °C and 10,000 rpm. After phase separation, approximately 6.0 mL of the supernatant was transferred to a Falcon tube containing 150.0 mg of PSA sorbent. The mixture was vortexed again for 3.0 min at 2500 rpm and centrifuged for an additional 10.0 min under the same conditions. The tubes were then placed in the freezer for 24 h. Once the aqueous phase had frozen, the organic extract containing the analytes was collected, filtered through a Cytiva Whatman MiniUniprep G2 vial with a 0.20 μm membrane filter (Marlborough, Massachusetts, USA), and injected into the GC–MS system (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig6">Figure 6</a>).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 6. Schematic representation of the extraction procedure using the QuEChERS–LTP procedure for pesticide extraction in cocoa powder samples." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg 223w," sizes="100vw" width="1458" height="1022"><h4>Results and Discussion</h4><h5>Evaluation of the Effect of Low and Ultralow Temperatures on the Analytical Response</h5>Studies reporting the use of LTP generally employ a conventional freezer, which typically reaches −18 ± 2 °C as the minimum temperature. In this equipment, effective phase separation can require 8 to 24 h. <a href="javascript:void(0);">(35−37)</a> In contrast, ultralow temperature freezers (ultrafreezers) can reach −80 °C, leading to a substantial reduction in partitioning time. In this study, tests performed with the conventional freezer achieved satisfactory partitioning after 24 h, whereas in the ultrafreezer, complete partitioning was observed in only 20 min.Considering the analytical response in terms of peak area (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>), higher signals were obtained when LTP was performed in a conventional freezer rather than an ultrafreezer. This behavior can be attributed to the partitioning mechanism. <a href="javascript:void(0);">(32)</a> Partitioning depends on cooling and the subsequent freezing of the aqueous phase. In the conventional freezer, the slower freezing rate provides sufficient time for the system to approach thermodynamic equilibrium, favoring analyte diffusion between phases. Under these conditions, analyte molecules have more time to migrate and distribute optimally before complete solidification. In contrast, the rapid freezing in the ultrafreezer may trap analytes in a nonideal distribution, reducing the efficiency of the partitioning process <a href="javascript:void(0);">(32)</a> (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>). According to these observations, the conventional freezer was selected for subsequent experiments.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 3. Comparison of chromatographic peak areas of pesticides after partitioning in the conventional freezer versus the ultrafreezer." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg 175w," sizes="100vw" width="996" height="891"><h5>Application to Real Samples</h5>Fifteen samples were analyzed in triplicate, comprising two from the State of Pará and 12 from the State of Bahia, located in the North and Northeast regions of Brazil, respectively. Among the 15 pesticides investigated, only permethrin isomers were quantified in four samples (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a>). The herbicide molinate was also detected in three samples; however, its concentration was below LOQ. Permethrin isomers concentrations ranged from 17.1 ± 0.3 to 49.6 ± 1.8 μg kg–1. These values are below the MRL established by European Union regulation, which is 100 μg kg–1. <a href="javascript:void(0);">(42)</a> Although permethrin is not permitted in the European Union, <a href="javascript:void(0);">(42)</a> it remains authorized for use as insecticide in Brazil, particularly in crops such as cotton, rice, coffee, citrus, cabbage, beans, tobacco, maize, soybean, tomato, wheat, and grape. <a href="javascript:void(0);">(13)</a> However, no MRL values have been established for cocoa beans under Brazilian legislation. <a href="javascript:void(0);">(13)</a> <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a> shows the concentration of detected compounds in the cocoa samples.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Table 3. Mean Concentrations (μg kg–1 ± Standard Deviation) of Target Pesticides Detected in This Study" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg 196w," sizes="100vw" width="1070" height="851">To assess method performance for pesticides not detected in the cocoa samples, one of the analyzed samples was fortified with a mixed standard solution at concentrations of 50, 250, and 500 μg kg–1. The fortified analytes were subsequently detected in the chromatograms presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Figures S2–S4</a>, indicating good response of the proposed method.<h4>Conclusions</h4>The QuEChERS–LTP procedure was successfully developed for the determination of 16 multiclass pesticide residues in cocoa beans. For the first time, ultralow temperature (−80 °C) was applied to accelerate the low-temperature partitioning process during pesticide extraction from cocoa beans. Nevertheless, conventional freezing at −12 °C proved to be more effective for the extraction of the target analytes.Evaluation of the matrix effect demonstrated that matrix-matched analytical curves, constructed in an analyte-free cocoa bean extract, were more effective in compensating for matrix interferences than the use of analyte protectants.The pyrethroid permethrin was quantified in four cocoa samples. However, the concentrations did not exceed the MRL established by European Union legislation.Overall, the QuEChERS–LTP procedure proved to be a promising approach for pesticide residue determination, as it requires smaller volumes of solvents and reagents, involves fewer cleanup and extraction steps, and shows strong potential for application to other complex matrices.

QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans

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The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) is a leading scientific institution in the Czech Republic, recognized internationally. Its primary mission is basic research in the fields of chemical biology and medicinal chemistry, organic and material oriented chemistry, chemistry of natural compounds, biochemistry and molecular biology, physical chemistry, theoretical chemistry, and analytical chemistry. 

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

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Phenomenex Strata SAX Solid Phase Extraction (SPE)

The quaternary amine group on this sorbent remains positively charged under all conditions, giving a strong anion-exchange mechanism of retention.

Ion-Exchange Solid Phase Extraction Sorbent (SPE)The quaternary amine group on this sorbent remains positively charged under all conditions, giving a strong anion-exchange mechanism of retention.<figure class="image"><img style="aspect-ratio:500/150;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Strata_sax_470d923b27.webp" alt="Phenomenex: Strata-SAX" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Strata_sax_470d923b27.webp 245w," sizes="100vw" width="500" height="150"></figure><ul><li>Surface Area (m²/g): -</li><li>Separation Mode: Ion Exchange</li><li>Particle Size: 55</li><li>Recommended Use: Extraction of weakly acidic compounds</li></ul><h4>Starting Method</h4><h5>Strata SAX – Strong Anion-Exchange</h5><ul><li>Condition: 1 mL Methanol</li><li>Equilibrate: 1 mL DI Water</li><li>Load: Pretreated sample, pH 6-7</li><li>Wash 1: 1 mL 25mM Ammonium Acetate Buffer, pH 6-7</li><li>Wash 2: 1 mL Methanol, dry under vacuum for 2-5 min</li><li>Elute: 1 mL 5% Formic Acid in Methanol</li></ul>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.

Phenomenex Strata Screen-A Solid Phase Extraction (SPE)

Incorporates the hydrophobic selectivity of a C8 phase and strong anion-exchange for the extraction of acidic drugs from biological matrices.

Mixed-Mode Solid Phase Extraction (SPE) SorbentIncorporates the hydrophobic selectivity of a C8 phase and strong anion-exchange for the extraction of acidic drugs from biological matrices.<figure class="image"><img style="aspect-ratio:500/150;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Strata_Screen_A_f370bdfd48.webp" alt="Phenomenex: Strata Screen-A" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Strata_Screen_A_f370bdfd48.webp 245w," sizes="100vw" width="500" height="150"></figure><ul><li>Surface Area (m²/g): -</li><li>Separation Mode: Multi-Mode</li><li>Particle Size: 55</li><li>Recommended Use: Extracts acidic drugs from biological matrices</li></ul><h4>Starting Method</h4><h5>Strata Screen-A Strong Anion-Exchange</h5><ul><li>Condition: 1 mL Methanol</li><li>Equilibrate: 1 mL Water</li><li>Load: Pretreated sample</li><li>Wash 1: 1 mL 25mM Ammonium Acetate Buffer, pH 6-7</li><li>Wash 2: 1 mL Methanol, dry under vacuum for 2-5 min</li><li>Elute: 1 mL 5% Formic Acid in Methanol</li></ul>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.

Phenomenex Strata Screen-C Solid Phase Extraction (SPE)

Incorporates the hydrophobic selectivity of a C8 phase and strong cation exchange for the extraction of basic drugs from biological matrices.

Strong Cation-Exchange Solid Phase Extraction (SPE)Incorporates the hydrophobic selectivity of a C8 phase and strong cation exchange for the extraction of basic drugs from biological matrices.<figure class="image"><img style="aspect-ratio:500/150;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Phenomenex_Strata_Screen_C_b60bb2b7e4.webp" alt="Phenomenex: Strata Screen-C" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Phenomenex_Strata_Screen_C_b60bb2b7e4.webp 245w," sizes="100vw" width="500" height="150"></figure><ul><li>Surface Area (m²/g): 500, m²/g, 500 m²/g</li><li>Separation Mode: Multi-Mode</li><li>Pore Size: 70</li><li>Particle Size: 55</li><li>Recommended Use: Extraction of basic drugs from biological matrixes</li></ul><h4>Starting Method</h4><h5>Strata Screen-C Strong Cation-Exchange</h5><ul><li>Condition: 1 mL Methanol</li><li>Equilibrate: 1 mL Acidified Water</li><li>Load: Pretreated sample (acidified)</li><li>Wash 1: 1 mL 0.1N HCl in Water</li><li>Wash 2: 1 mL 0.1N HCl in Methanol, dry under vacuum for 2-5 min</li><li>Elute: 1 mL 5 % NH4OH in Methanol</li></ul>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.

Phenomenex Strata Screen-C GF Solid Phase Extraction (SPE)

Optimized for gravity flow, this sorbent offers hydrophobic selectivity from a C8 phase and strong cation-exchange properties for the extraction of basic drugs.

Strong Cation-Exchange Solid Phase Extraction (SPE)Optimized for gravity flow, this sorbent offers hydrophobic selectivity from a C8 phase and strong cation-exchange properties for the extraction of basic drugs from biological matrixes. Offers the selectivity of Screen-C in a gravity flow particle size for viscous samples.<h4>Starting Method</h4><h5>Strata Screen-C GF Strong Cation-Exchange</h5><ul><li>Condition: 1 mL Methanol</li><li>Equilibrate: 1 mL Acidified Water</li><li>Load: Pretreated sample (acidified)</li><li>Wash 1: 1 mL 0.1N HCl in Water</li><li>Wash 2: 1 mL 0.1N HCl in Methanol, dry under vacuum for 2-5 min</li><li>Elute: 1 mL 5 % NH4OH in Methanol</li></ul>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.

Organomation NITRO-GEN Nitrogen Generator

The NITRO-GEN generator was developed with Organomation’s nitrogen evaporators in mind to provide nitrogen generation for sample concentration.

The NITRO-GEN generator was developed with Organomation’s nitrogen evaporators in mind to provide nitrogen generation for sample concentration. The generator is lightweight and easy to set up, requiring only a source of compressed air to run. This unit is an ideal choice for labs with an in-house compressed air source.The generator uses a hollow-fiber membrane to convert compressed air to a stream of 95-99% pure nitrogen gas. The hollow-fiber membrane consists of a series of narrow, semipermeable tubes in a porous membrane. As compressed air travels through the fibers, oxygen and water vapor permeate the membrane and are vented off, leaving a steam of high purity nitrogen gas. At up to 99% purity, the resulting nitrogen gas stream can be used in a variety of sample preparation applications.<h4>NITRO-GEN</h4>The NITRO-GEN produces up to 20 L/min of nitrogen gas and is recommended for evaporation of up to 48 sample positions.&nbsp;<h4>Standard features</h4><ul><li>Adjustable outlet pressure regulator, 0-100 psi</li><li>Dual Stage clean air filtration system</li><li>Requires an oil-less compressed air source</li></ul><h4>Advantages</h4><ul><li>Quick Start-Up Time - Nitrogen is produced instantly, no heat up time</li><li>Saves Energy - No electrical power needed</li><li>Engineered Design - Life expectancy is more than 10 years</li><li>Low Maintenance - Serviceable clean air filter</li><li>Compact and Lightweight - Small footprint conserves valuable bench space</li><li>Reduced CO2 Emissions - No heaters, less energy required</li></ul><h4>Specification</h4><h5>Key Features:</h5><ul><li>Flow Rate: Up to 20 L/min</li><li>Technology: Hollow-fiber membrane</li><li>Output Pressure: Adjustable 0 – 100 PSI</li><li>Electrical Requirements: None (no power required)</li><li>Noise Level: &lt; 40 dBA (virtually silent when connected to an instrument)</li></ul><h5>Inlet Air Requirements:</h5><ul><li>Maximum Inlet Pressure: 150 PSI (10.3 bar)</li><li>Particulate Filtration: ≤ 0.01 µm</li><li>Oil Vapor Content: &lt; 0.01 mg/m³ (&lt; 0.01 ppm)</li><li>Relative Humidity: &lt; 100% (non-condensing)</li><li>Air Quality: Clean, contaminant-free air</li></ul><h5>Environmental Conditions:</h5><ul><li>Operating Temperature: 36–122 °F (2–50 °C)</li><li>Ambient Pressure: Atmospheric</li></ul><h5>Dimensions &amp; Weight:</h5><ul><li>Size (W × D × H): 9.5 × 8 × 19.5 in (241 × 203 × 495 mm)</li><li>Weight: 13.25 lbs (6 kg)</li></ul>Warranty: 1 year

Organomation ROT-X-TRACT-S Soxhlet extractor

Unlike traditional wire or sand baths which are used to heat receiving flasks, the ROT-X-TRACT-S uses a water steam bath which provides gentle even heat to delicate samples.

Soxhlet extraction is ideal for extracting soluble analytes from a solid sample into an organic solvent. Unlike traditional wire or sand baths which are used to heat receiving flasks, the ROT-X-TRACT-S uses a water steam bath which provides gentle even heat to delicate samples.The ROT-X-TRACT-S rotary Soxhlet extractors can accommodate up to 8 or 10 Soxhlet extractors. The bath cover disc holes can accommodate round sample flasks from 125 ml-1 L. Models 13070 and 13090 can accommodate smaller 250 mL flasks, while model 13008 can accommodate larger 500 mL flasks. A wide range of sample sizes and quantities make this instrument ideal for Soxhlet extraction of samples in any lab.<h4>Standard features</h4><ul><li>Stainless steel construction</li><li>Stepped bath rim and cover disk seals steam chamber</li><li>Each condenser water line attached to centrally located water manifold</li><li>Laboratory grade materials stand up to organic solvents</li></ul><h4>OPTIONS (Add to main Cat# when purchasing)</h4><ul><li>Positive pressure type Z purged bath (Option Code -Z), Cat# 13070/13090/13008-Z</li><li>240V wiring and plug (Option Code -2), Cat# 13070/13090/13008-2</li></ul><h4>ACCESSORIES</h4><ul><li>P1332: O-rings for S-EVAP/RXT water manifold</li><li>All associated glassware</li><li>Rotary clamp manifold assembly</li><li>Bath cover disks</li></ul><h4>Specification</h4><h5>Model 13070 – 8 Position, 37 mm Extractors</h5>Ideal for labs using 250 mL round-bottom flasks, this model features a medium-size 12-inch ID water bath (Model 9125) and supports GS3137 or GS3129 glassware.<ul><li>Overall Dimensions: 18 × 16 × 34 in (46 × 41 × 86 cm)</li><li>Heating Power: 900 W</li><li>Temperature Control: Dial thermostat with ±2 °C accuracy</li></ul><h5>Model 13090 – 10 Position, 37 mm Extractors</h5>This high-throughput option also works with 250 mL flasks and uses a larger 16-inch ID bath (Model 16165) to accommodate 10 samples simultaneously.<ul><li>Overall Dimensions: 24 × 19 × 34 in (61 × 48 × 86 cm)</li><li>Heating Power: 1600 W</li><li>Temperature Control: Dial thermostat with ±2 °C accuracy</li></ul><h5>Model 13008 – 8 Position, 50 mm Extractors</h5>For larger sample volumes, Model 13008 supports 500 mL round-bottom flasks and includes a 16-inch bath with higher accuracy temperature control. It uses GS3150 glassware and larger 55/50 extractor joints for robust handling of bigger samples.<ul><li>Overall Dimensions: 24 × 19 × 37 in (61 × 48 × 94 cm)</li><li>Heating Power: 1600 W</li><li>Temperature Control: Dial thermostat with ±0.5 °C accuracy</li></ul><h5>Key Shared Features</h5><ul><li>Extractor Joint Sizes:<ul><li>13070 &amp; 13090: 45/50, 24/40</li><li>13008: 55/50, 24/40</li></ul></li><li>Condenser Options:<ul><li>Standard: Allihn</li><li>Optional: Friedrichs (for enhanced cooling performance)</li></ul></li><li>Condenser Joint Size: 55/50</li><li>Bath Temperature Range: 40–100 °C</li><li>Heating Medium: Water</li><li>Bath Inside Dimensions:<ul><li>13070: 12 × 4.5 in (30.5 × 11.4 cm)</li><li>13090 &amp; 13008: 16 × 4.5 in (40.6 × 11.4 cm)</li></ul></li></ul>

Organomation 12 Position N-EVAP Nitrogen Evaporator

The 12 position N-EVAP nitrogen evaporator is a compact unit that allows for up to 12 samples to be evaporated simultaneously.  At each individual sample position, the gas flow can be controlled via a precision needle valve.

The 12 position N-EVAP nitrogen evaporator (cat# 11155) is a compact unit that allows for up to 12 samples to be evaporated simultaneously. At each individual sample position, the gas flow can be controlled via a precision needle valve. This is ideal for the simultaneous evaporation of samples with varying evaporation end points. The sample tray has a spring tensioner which allows any test tube between 10-30 mm to be processed without any modifications to the instrument. An optional small sample holder allows samples with an outside diameter of 5-16 mm to be processed.First introduced in 1959 as The Meyer N-EVAP, the 12 position N-EVAP (cat# 11155) was the first nitrogen dryer created by Organomation. It has proven to be an extremely durable, time tested and highly affordable member of Organomation’s N-EVAP line. These economical units provide controlled concentration of sample vials through the application of nitrogen gas within a heated water bath. The N-EVAP’s circular rotating design permits each sample to be accessible from the front of the instrument for easy insertion and retrieval. The chrome plated needle valves are individually milled from solid brass, enabling precise, uniform adjustments for your nitrogen blow down. This promotes efficient and safe sample reduction with minimal nitrogen waste.<ul><li>Small Footprint: N-EVAP Model 111 requires under one square foot of bench space</li><li>Flexible: An adjustable sample holder design fits a wide variety of sample tubes and vials at once</li><li>Customizable: Options are available for use with acidic or flammable solvents, heat- or water-sensitive samples, and more</li><li>Individualized Control: Optimize evaporation of diverse samples with individual gas flow control at each vial</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Organomation_12_Position_N_EVAP_Nitrogen_Evaporator_5_339151fb9f.jpg" alt="Organomation 12 Position N-EVAP Nitrogen Evaporator ." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Organomation_12_Position_N_EVAP_Nitrogen_Evaporator_5_339151fb9f.jpg 156w," sizes="100vw" width="1400" height="1400"><h3>STANDARD FEATURES</h3><ul><li>Nitrogen filter</li><li>Adjustable flow meter, 0-10 LPM</li><li>High pressure phthalate free tubing for safety</li><li>High temperature limit switch for safety</li><li>Dual band spring hoist assembly (except in dry bath model)</li><li>Precision needle valve tube assembly</li><li>Needles, 4 inch x 19 gauge with chrome plated brass hub and stainless steel shaft</li></ul><h3>OPTIONS&nbsp;</h3><ul><li>220v wiring harness (Option Code# -2), Cat# 11155-2</li><li>Z-Purge/positive pressure purge case (Option Code# -Z), Cat# 11155-Z</li><li>Acid resistant coating on instrument and needles (Option Code# -RT), Cat# 11155-RT</li></ul><h3>SPECS</h3><h4>12p N-EVAP (Water Bath)</h4><ul><li>Bath Type: Water</li><li>Instrumental Catalog Number: 11155</li><li>Number of Sample Positions: 12</li><li>Overall Dimension (w x d x h): 13 x 11 x 31 in / 33 x 28 x 79 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 5–16 mm OD</li><li>Gas Flow Meter: 0–10 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Standard Gas Input Range: 20–30 psig</li><li>Optional Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating (Option Code -RT): Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 5585</li><li>Heating Medium: Water</li><li>Inside Dimensions (Diameter × Depth): 8.5 × 4.5 in / 21.6 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 13 × 11 × 7 in / 33 × 28 × 18 cm</li><li>Total Wattage: 550 W</li><li>Bath Temperature Range: 30–90 °C</li><li>Temperature Controller Type: Mechanical Thermostat</li><li>Controller Accuracy: ± 2 °C</li></ul><h4>12p N-EVAP (Dry Bath)</h4><ul><li>Bath Type: Dry</li><li>Instrumental Catalog Number: 11155-DA</li><li>Number of Sample Positions: 12</li><li>Overall Dimension (w x d x h): 13 x 11 x 27.5 in / 33 x 28 x 70 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 5–16 mm OD</li><li>Gas Flow Meter: 0–10 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: None/Fixed</li><li>Rotating, Leak Tight Gas Fitting: N/A</li><li>Standard Gas Input Range: 20–30 psig</li><li>Optional Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating (Option Code -RT): Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 5085</li><li>Heating Medium: Aluminum Beads (Glass Beads in RT Models)</li><li>Inside Dimensions (Diameter × Depth): 8.5 × 4.5 in / 21.6 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 13 × 11 × 7 in / 33 × 28 × 18 cm</li><li>Total Wattage: 500 W</li><li>Bath Temperature Range: 40–130 °C</li><li>Temperature Controller Type: Mechanical Thermostat</li><li>Controller Accuracy: ± 2 °C</li></ul><h4>12p N-EVAP (No Bath)</h4><ul><li>Bath Type: None</li><li>Instrumental Catalog Number: 11155-O</li><li>Number of Sample Positions: 12</li><li>Overall Dimension (w x d x h): 12 × 8 × 31 in / 33 × 28 × 79 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 5–16 mm OD</li><li>Gas Flow Meter: 0–10 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Standard Gas Input Range: 20–30 psig</li><li>Optional Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating (Option Code -RT): Optional</li></ul><h3>MODELS</h3><h5>Catalog Number &nbsp;/&nbsp;&nbsp;&nbsp;Bath Type</h5><ul><li>11155: Water Bath</li><li>11155-NT: No Teflon, Water Bath*</li><li>11155-DA: Dry Bath</li><li>11155-O: No Bath</li></ul>* No Teflon (-NT) units designed for PFAS analysis using EPA methods 533, 537 and 537.1. **All “-O” models come with a base and stand assembly instead of a heated bath. These instruments are designed for evaporation procedures performed at ambient temperature.<h3>ACCESSORIES</h3><ul><li>Small vessel sample holder, for vial outside diameters of 5-16 mm (cat# NA1132)</li><li>Nitrogen generator (cat# NA1955)</li><li>Pasteur pipette adapters (cat# NA0636)</li><li>Pressure reducing regulator 0-160 psi (cat# NA0630)</li><li>High temperature silicone fluid (cat# NA1240)</li><li>Various needle sizes and gauges</li></ul><h3>REPLACEMENT PARTS</h3><ul><li>P0627: Valve Tube Assembly – Post 1997</li><li>P0607: Luer &amp; washer for N-EVAP valve tube</li><li>P0634: Tube Fitting nylon 3 part for N-EVAP valve tube</li></ul>

Organomation 24 Position N-EVAP Nitrogen Evaporator

The 24 position N-EVAP is our most adaptable benchtop evaporator. The basic model offers all of the standard features from our N-EVAP line. Additionally, the 24 position N-EVAP offers the most customizable options for your sample preparation needs. 

The 24 position N-EVAP is our most adaptable benchtop evaporator. The basic model offers all of the standard features from our N-EVAP line. Additionally, the 24 position N-EVAP offers the most customizable options for your sample preparation needs. The standard sample holder can accommodate samples with an outside diameter of 10-30 mm. However, with the optional 8 position large sample holder, vials with an outside diameter of 30-70 mm can be processed. The 24 position N-EVAP test tube evaporator can also be upgraded to include digital controls for heat and time with the addition of the side control box (Option code -CB).These economical units provide controlled concentration of sample vials through the application of nitrogen gas within a heated water bath. The dual band spring hoist assembly provides a simple and effective means of removing samples from the heated water bath. The N-EVAP’s circular rotating design permits each sample to be accessible from the front of the instrument for easy insertion and retrieval. The chrome plated needle valves are individually milled from solid brass, enabling precise, uniform adjustments for your nitrogen blow down. This promotes efficient and safe sample reduction with minimal nitrogen waste. Time tested technology and proven construction ensure a long lasting, user-friendly experience.<ul><li>Gentle: N-EVAP nitrogen evaporators combine nitrogen blow down with a heated bath to gently concentrate delicate samples</li><li>Flexible: An adjustable sample holder design fits a wide variety of sample tubes and vials at once</li><li>Customizable: A large sample holder option can be added to accommodate vials with a larger outside diameter up to 70 mm</li><li>Individualized Control: Optimize evaporation of diverse samples with individual gas flow control at each vial</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Organomation_24_Position_N_EVAP_Nitrogen_Evaporator_2_18a854b63f.jpg" alt="Organomation 24 Position N-EVAP Nitrogen Evaporator ." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Organomation_24_Position_N_EVAP_Nitrogen_Evaporator_2_18a854b63f.jpg 156w," sizes="100vw" width="1400" height="1400"><h3>STANDARD FEATURES</h3><ul><li>Nitrogen filter</li><li>Adjustable flow meter, 0-20 LPM</li><li>High pressure phthalate free tubing for safety</li><li>High temperature limit switch for safety</li><li>Dual band spring hoist assembly (except in dry bath model)</li><li>Precision needle valve tube assembly</li><li>Needles, 4 inch x 19 gauge with chrome plated brass hub and stainless steel shaft</li></ul><h3>OPTIONS&nbsp;</h3><ul><li>220v wiring harness (Option Code# -2), Cat# 11250-2</li><li>Z-Purge/positive pressure purge case (Option Code# -Z), Cat# 11250-Z</li><li>Acid resistant coating on instrument and needles (Option Code# -RT), Cat# 11250-RT</li><li>Side control box with built-in digital controller, timer, and pressure regulator (Option Code -CB), Cat# 11250-CB</li></ul><h3>SPECS</h3><h4>24 Position N-EVAP (Water Bath)</h4><ul><li>Bath Type: Water</li><li>Instrumental Catalog Number: 11250</li><li>Number of Sample Positions: 24</li><li>Overall Dimension (w × d × h): 16 × 15 × 33 in / 41 × 38 × 84 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 30–70 mm OD</li><li>Gas Flow Meter: 0–20 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Standard Gas Input Range: 20–30 psig</li><li>Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating: Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 9125</li><li>Heating Medium: Water</li><li>Inside Dimensions (Diameter × Depth): 12.0 × 4.5 in / 30.5 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 16 × 15 × 7 in / 41 × 38 × 18 cm</li><li>Total Wattage: 900 W</li><li>Bath Temperature Range: 30–90 °C</li><li>Temperature Controller Type: Mechanical Thermostat</li><li>Controller Accuracy: ±2 °C</li></ul><h4>24 Position N-EVAP (Dry Bath)</h4><ul><li>Bath Type: Dry</li><li>Instrumental Catalog Number: 11250-DA</li><li>Number of Sample Positions: 24</li><li>Overall Dimension (w × d × h): 16 × 15 × 27.5 in / 41 × 38 × 70 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 30–70 mm OD</li><li>Gas Flow Meter: 0–20 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: None/Fixed</li><li>Rotating, Leak Tight Gas Fitting: N/A</li><li>Standard Gas Input Range: 20–30 psig</li><li>Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating: Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 5125</li><li>Heating Medium: Aluminum Beads (Glass Beads in RT Models)</li><li>Inside Dimensions (Diameter × Depth): 12.0 × 4.5 in / 30.5 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 16 × 15 × 7 in / 41 × 38 × 18 cm</li><li>Total Wattage: 540 W</li><li>Bath Temperature Range: 40–130 °C</li><li>Temperature Controller Type: Mechanical Thermostat</li><li>Controller Accuracy: ±2 °C</li></ul><h4>24 Position N-EVAP (No Bath)</h4><ul><li>Bath Type: None</li><li>Instrumental Catalog Number: 11250-O</li><li>Number of Sample Positions: 24</li><li>Overall Dimension (w × d × h): 16 × 15 × 31.75 in / 41 × 38 × 81 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Test Tube Range (Optional Sample Holder): 30–70 mm OD</li><li>Gas Flow Meter: 0–20 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Standard Gas Input Range: 20–30 psig</li><li>Gas Input Range with Optional Pressure Reducing Regulator: 30–160 psig</li><li>Acid Resistant Coating: Optional</li></ul><h3>MODELS</h3><h5>Catalog Number &nbsp;/&nbsp;&nbsp;&nbsp;Bath Type</h5><ul><li>11250: Water Bath</li><li>11250-NT: No Teflon, Water Bath*</li><li>11250-DA: Dry Bath</li><li>11250-O: No Bath**</li></ul>* No Teflon (-NT) units designed for PFAS analysis using EPA methods 533, 537 and 537.1. **All “-O” models come with a base and stand assembly instead of a heated bath. These instruments are designed for evaporation procedures performed at ambient temperature.<h3>ACCESSORIES</h3><ul><li>Large vessel sample holder, 8 positions, for vial outside diameters of 30-70 mm (cat# NA1228)</li><li>Nitrogen generator (cat# NA1955)</li><li>Pasteur pipette adapters (cat# NA0636)</li><li>Pressure reducing regulator 0-160 psi (cat# NA0630)</li><li>High temperature silicone fluid (cat# NA1240)</li><li>Various needle sizes and gauges</li></ul><h3>REPLACEMENT PARTS</h3><ul><li>P0627: Valve Tube Assembly – Post 1997</li><li>P0607: Luer &amp; washer for N-EVAP valve tube</li><li>P0634: Tube Fitting nylon 3 part for N-EVAP valve tube</li></ul>

Organomation 34 Position N-EVAP Nitrogen Evaporator

Our 34-position nitrogen evaporator (cat# 11634) offers a large number of sample positions, without compromising any of the classic N-EVAP features. 

Our 34-position nitrogen evaporator (cat# 11634) offers a large number of sample positions, without compromising any of the classic N-EVAP features. This time-tested, durable system provides one of the least expensive prices per position of all our N-EVAPs. The evaporative system, along with the standard flow control and pressure reducing regulator, enables the operator to achieve the desired level of concentration with efficient nitrogen usage. Our unique dual band spring hoist assembly ensures easy and effective operator use.Additionally, the 34 position N-EVAP includes a side control box, which provides timed and digitally controlled water bath temperatures to produce even evaporation rates. The pressure regulator and timer combine to allow timed automatic gas flow cut off which slows evaporation to a minimum once the timed cycle has been completed. In order to prevent damage to delicate samples, the timer also provides the option for the heat to shut off once the cycle is complete.<ul><li>Gentle: N-EVAP nitrogen evaporators combine nitrogen blow down with a heated bath to gently concentrate delicate samples</li><li>Flexible: An adjustable sample holder design fits a wide variety of sample tubes and vials at once</li><li>Precise: Digital controls allow exact temperature regulation</li><li>Individualized Control: Optimize evaporation of diverse samples with individual gas flow control at each vial</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Organomation_34_Position_N_EVAP_Nitrogen_Evaporator_3_04176ee4e2.jpg" alt="Organomation 34 Position N-EVAP Nitrogen Evaporator." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Organomation_34_Position_N_EVAP_Nitrogen_Evaporator_3_04176ee4e2.jpg 156w," sizes="100vw" width="1400" height="1400"><h3>STANDARD FEATURES</h3><ul><li>Nitrogen filter</li><li>Adjustable flow meter, 0-30 LPM</li><li>Built-in pressure reducing regulator</li><li>Side control box</li><li>Digital temperature controller</li><li>Electronic timer</li><li>Safety control cover plate</li><li>High pressure phthalate free tubing&nbsp;</li><li>High temperature limit switch for safety</li><li>Dual band spring hoist assembly&nbsp;</li><li>Precision needle valve tube assembly</li><li>Needles, 4 inch x 19 gauge with chrome plated brass hub and stainless steel shaft</li></ul><h3>OPTIONS&nbsp;</h3><ul><li>220v wiring harness (Option Code# -2), Cat# 111634-2</li><li>Z-Purge/positive pressure purge case (Option Code# -Z), Cat# 11634-Z</li><li>Acid resistant coating on instrument and needles (Option Code# -RT), Cat# 11634-RT</li></ul><h3>SPECS</h3><h4>34 Position N-EVAP (Water Bath)</h4><ul><li>Bath Type: Water</li><li>Instrumental Catalog Number: 11634</li><li>Number of Sample Positions: 34</li><li>Overall Dimension (w × d × h): 24 × 19 × 34 in / 61 × 48 × 86 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Gas Flow Meter: 0–30 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Built-in Nitrogen Gauge Input: 30–110 psig</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Acid Resistant Coating: Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 13165</li><li>Heating Medium: Water</li><li>Inside Dimensions (Diameter × Depth): 16.0 × 4.5 in / 40.6 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 24 × 19 × 6 in / 61 × 48 × 15 cm</li><li>Total Wattage: 1300 W</li><li>Bath Temperature Range: 30–90 °C</li><li>Temperature Controller Type: Digital Electronic with LED Display</li><li>Controller Accuracy: ±2 °C</li><li>Side Mounted Control Box with Timer for Nitrogen &amp; Heat: Standard</li></ul><h4>34 Position N-EVAP (No Bath)</h4><ul><li>Bath Type: None</li><li>Instrumental Catalog Number: 11634-O</li><li>Number of Sample Positions: 34</li><li>Overall Dimension (w × d × h): 19 × 17 × 32 in / 48 × 43 × 81 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Single Ring</li><li>Test Tube Range (Standard Sample Holder): 10–30 mm OD</li><li>Gas Flow Meter: 0–30 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Built-in Nitrogen Gauge Input: 30–110 psig</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Acid Resistant Coating: Optional</li></ul><h3>MODELS</h3><h5>Catalog Number &nbsp;/&nbsp;&nbsp;&nbsp;Bath Type</h5><ul><li>11634: Water</li><li>11634-O: No Bath*</li></ul>*All “-O” models come with a base and stand assembly instead of a heated bath. These instruments are designed for evaporation procedures performed at ambient temperature.<h3>ACCESSORIES</h3><ul><li>Nitrogen generator (cat# NA1955)</li><li>Pasteur pipette adapters (cat# NA0636)</li><li>High temperature silicone fluid (cat# NA1240)</li><li>Various needle sizes and gauges</li></ul><h3>REPLACEMENT PARTS</h3><ul><li>P0627: Valve Tube Assembly – Post 1997</li><li>P0607: Luer &amp; washer for N-EVAP valve tube</li><li>P0634: Tube Fitting nylon 3 part for N-EVAP valve tube</li></ul>

Organomation 45 Position N-EVAP Nitrogen Evaporator

Our 45-position nitrogen evaporator offers the largest number of sample positions in our N-EVAP line. 

Our 45-position nitrogen evaporator (Catalog # 11645) offers the largest number of sample positions in our N-EVAP line. The sample holder has dual circular rings. The outer ring has 30 positions and can accommodate samples with an outside diameter of 10-19 mm The inner ring has 15 positions and can accommodate samples with an outside diameter of 16-30 mm and a minimum height of 70 mm.This time-tested, durable system provides the least expensive price per position of all our N-EVAPs. The evaporative system, along with the standard flow control and pressure reducing regulator, enables the operator to achieve the desired level of concentration with efficient nitrogen usage. Our unique dual band spring hoist assembly ensures easy and effective operator use. Additionally, the 45 position N-EVAP includes a side control box. Timed, digitally controlled water bath temperatures provide even evaporation rates. The pressure regulator and timer combine to allow timed automatic gas flow cut off which slows evaporation to a minimum once the timed cycle has been completed. The heat can also be shut off with the gas after a timed cycle.<ul><li>Gentle: N-EVAP nitrogen evaporators combine nitrogen blow down with a heated bath to gently concentrate delicate samples</li><li>Flexible: An adjustable sample holder design fits a wide variety of sample tubes and vials at once</li><li>Precise: Digital controls allow exact temperature regulation</li><li>Individualized Control: Optimize evaporation of diverse samples with individual gas flow control at each vial</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Organomation_45_Position_N_EVAP_Nitrogen_Evaporator_5_20078e3969.jpg" alt="Organomation: 45 Position N-EVAP Nitrogen Evaporator." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Organomation_45_Position_N_EVAP_Nitrogen_Evaporator_5_20078e3969.jpg 156w," sizes="100vw" width="1400" height="1400"><h3>STANDARD FEATURES</h3><ul><li>Nitrogen filter</li><li>Adjustable flow meter, 0-30 LPM</li><li>Built-in pressure reducing regulator</li><li>Side control box</li><li>Digital temperature controller</li><li>Electronic timer</li><li>Safety control cover plate</li><li>High pressure phthalate free tubing&nbsp;</li><li>High temperature limit switch for safety</li><li>Dual band spring hoist assembly&nbsp;</li><li>Precision needle valve tube assembly</li><li>Needles, 4 inch x 19 gauge with chrome plated brass hub and stainless steel shaft</li></ul><h3>OPTIONS&nbsp;</h3><ul><li>220v wiring harness (Option Code# -2), Cat# 11645-2</li><li>Z-Purge/positive pressure purge case (Option Code# -Z), Cat# 11645-Z</li><li>Acid resistant coating on instrument and needles (Option Code# -RT), Cat# 11645-RT</li></ul><h3>SPECS</h3><h4>45 Position N-EVAP (Water Bath)</h4><ul><li>Bath Type: Water</li><li>Instrumental Catalog Number: 11645</li><li>Number of Sample Positions: 45</li><li>Overall Dimension (w × d × h): 24 × 19 × 34 in / 61 × 48 × 86 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Dual Rings</li><li>Outer Circle Sample Holder Test Tube Range: 10–19 mm OD</li><li>Inner Circle Sample Holder Test Tube Range: 16–30 mm OD; &gt;70 mm height</li><li>Gas Flow Meter: 0–30 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Built-in Nitrogen Gauge Input: 30–110 psig</li><li>Acid Resistant Coating: Optional</li></ul><h5>Heating Device Specs</h5><ul><li>Model Number: 13165</li><li>Heating Medium: Water</li><li>Inside Dimensions (Diameter × Depth): 16.0 × 4.5 in / 40.6 × 11.4 cm</li><li>Outside Dimensions (w × d × h): 24 × 19 × 6 in / 61 × 48 × 15 cm</li><li>Total Wattage: 1300 W</li><li>Bath Temperature Range: 30–90 °C</li><li>Temperature Controller Type: Digital Electronic with LED Display</li><li>Controller Accuracy: ±2 °C</li><li>Side Mount Control Box with Timer for Nitrogen &amp; Heat: Standard</li></ul><h4>45 Position N-EVAP (No Bath)</h4><ul><li>Bath Type: None</li><li>Instrumental Catalog Number: 11645-O</li><li>Number of Sample Positions: 45</li><li>Overall Dimension (w × d × h): 24 × 19 × 32 in / 61 × 48 × 81 cm</li><li>Sample Holder Layout: Circular</li><li>Gas Manifold Layout: Dual Rings</li><li>Outer Circle Sample Holder Test Tube Range: 10–19 mm OD</li><li>Inner Circle Sample Holder Test Tube Range: 16–30 mm OD; 70 mm height</li><li>Gas Flow Meter: 0–30 L/min</li><li>Stainless Steel Needles (Length × Gauge): 4.0 in × 19 ga / 102 mm × 19 ga</li><li>Sample Tray Lift Mechanism: Dual Band Spring Hoist Assembly</li><li>Rotating, Leak Tight Gas Fitting: Standard</li><li>Built-in Nitrogen Gauge Input: 30–110 psig</li><li>Acid Resistant Coating: Optional</li></ul><h3>MODELS</h3><h5>Catalog Number &nbsp;/&nbsp;&nbsp;&nbsp;Bath Type</h5><ul><li>11645: Water Bath</li><li>11634-O: No Bath*</li></ul>*All “-O” models come with a base and stand assembly instead of a heated bath. These instruments are designed for evaporation procedures performed at ambient temperature.<h3>ACCESSORIES</h3><ul><li>Nitrogen generator (cat# NA1955)</li><li>Pasteur pipette adapters (cat# NA0636)</li><li>High temperature silicone fluid (cat# NA1240)</li><li>Various needle sizes and gauges</li></ul><h3>REPLACEMENT PARTS</h3><ul><li>P0627: Valve Tube Assembly – Post 1997</li><li>P0607: Luer &amp; washer for N-EVAP valve tube</li><li>P0634: Tube Fitting nylon 3 part for N-EVAP valve tube</li></ul>

Products focused on Sample Preparation - page 3

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