EU Regulation 396/2005: Pesticide Residue Testing and the Critical Role of QuEChERS Evaporation in Food Safety

<div><div>Researchers led by <a target="_blank" rel="noopener noreferrer" href="https://kudova.group.uochb.cz/en">Eva Kudová</a> from IOCB Prague and Jitka Viktorová from UCT Prague have identified new androstane-based steroid derivatives that can significantly improve the effectiveness of existing antibiotics against multidrug-resistant Staphylococcus aureus.</div></div><div>The team screened dozens of natural steroidal hormones and synthetic derivatives to see whether they could block bacterial efflux pumps – mechanisms that bacteria use to eject antibiotics and survive treatment. Two compounds emerged as particularly promising: they inhibited efflux pumps and lowered the effective doses of antibiotics such as ciprofloxacin and erythromycin.Further analysis showed that one of the compounds also suppressed genes linked to bacterial virulence. Another key finding is that the most active molecules are non-toxic to human immune cells and showed no detectable endocrine activity, suggesting a favorable safety profile.These findings support the idea that rationally designed steroid-based molecules could act as antibiotic adjuvants, helping existing drugs overcome bacterial resistance.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/IOCB_Prague_Steroidal_hormones_and_neurosteroids_novel_therapeutic_strategies_in_bacterial_infections_8e5d2a7b48.jpg" alt="IOCB Prague: Steroidal hormones and neurosteroids – novel therapeutic strategies in bacterial infections" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_IOCB_Prague_Steroidal_hormones_and_neurosteroids_novel_therapeutic_strategies_in_bacterial_infections_8e5d2a7b48.jpg 222w," sizes="100vw" width="1258" height="886"><blockquote><h4>Original Article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.sciencedirect.com/science/article/pii/S0223523426001613?via%3Dihub">Steroidal hormones and neurosteroids - novel therapeutic strategies in bacterial infections: Design, synthesis, and biological evaluation</a></h4>Daniela Brdová, Bára Křížkovská, Jan Špaček, Zdeněk Míchal, Eva Jablonská, Ondřej Strnad, Hana Chodounská, Eszter Szánti-Pintér, Marina Morozovová, Václav Hanžl, Jan Tkadlec, Martijn Riool, Jan Lipov, Jitka Viktorová, Eva Kudová&nbsp;Eur. J. Med. Chem., 2026, 308, 118716<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1016/j.ejmech.2026.118716">https://doi.org/10.1016/j.ejmech.2026.118716</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>The global rise of antibiotic resistance necessitates novel therapeutic strategies for infectious diseases. Inhibition of bacterial efflux pumps, which contribute to multidrug resistance, represents a promising approach to restore or even increase the efficacy of existing antibiotics. Using fluorescence-based ethidium bromide accumulation, broth microdilution, and checkerboard assays, we evaluated 26 endogenous steroidal hormones and neurosteroids, along with 30 synthetic derivatives, for their ability to enhance antibiotic susceptibility in multidrug-resistant Staphylococcus aureus. Structure-activity relationship analysis identified compounds 13 and 16 as lead candidates, exhibiting strong efflux pump inhibition and marked reductions in the minimum inhibitory concentrations of ciprofloxacin and erythromycin. Both compounds showed additive effects in checkerboard assays. Modifications at C-3 (polar substitution) and C-17 (3α,5β-stereochemistry and nonpolar substitution) were essential for potent efflux inhibition and sensitization, although these modifications were not additive when combined. Transcriptome analysis further revealed that compound 13 significantly downregulated S. aureus virulence-associated genes when administered alone or in combination with antibiotics. Cytotoxicity assessment in human peripheral blood mononuclear cells and receptor transactivation assays for estrogen, androgen, and progesterone receptors indicated that the most active derivatives were non-toxic and lacked detectable endocrine activity, suggesting a favorable safety profile. Overall, these findings support the concept that rationally designed andostane-based steroidal scaffolds can function as competitive bacterial efflux pump inhibitors and serve as potential antibiotic adjuvants to mitigate efflux-mediated resistance.<h4>Instrumentation</h4><h5>Structural characterization</h5><ul><li>AVANCE III 400 MHz NMR spectrometer (Bruker)</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=3&amp;search=LTQ+Orbitrap+XL">LTQ Orbitrap XL HRMS</a> (Thermo Fisher Scientific, ESI)</li></ul></div>

Steroidal hormones and neurosteroids – novel therapeutic strategies in bacterial infections

Metformin is currently the first-line oral drug of choice for the treatment of type 2 diabetes. It reduces glucose production in the liver, improves tissue sensitivity to insulin, and does not cause weight gain or hypoglycemia, which sets it apart from some other antidiabetic drugs. Moreover, its long-term beneficial effects on the risk of cardiovascular complications and mortality in people with type 2 diabetes have been well established. Researchers from the Institute of Physiology CAS (IPHYS) have identified a new group of blood metabolites that could help physicians objectively monitor whether patients with type 2 diabetes are taking their metformin as prescribed.<h4>New biomarkers for metformin use</h4>A team led by Tomáš Čajka from the Laboratory of Translational Metabolism at IPHYS analyzed plasma samples from 637 patients with type 2 diabetes treated with metformin and 143 non-diabetic controls using advanced metabolomics and lipidomics. Among 614 detected metabolites, they identified five from the group of N-lactoyl-amino acids (e.g. N‑lactoyl-phenylalanine), which had previously been seen as unknown signals due to missing reference spectra in databases. The levels of these metabolites in the blood closely reflected the plasma concentrations of metformin. In patients with the highest metformin exposure, the concentrations of these metabolites were up to 7.2 times higher than in controls.<h4>A sensitive “fingerprint” of the drug’s effect</h4>N-Lactoyl-amino acids are formed in cells by combining lactate and amino acids, thus reflecting the metformin-induced changes in cellular energy metabolism. “Importantly, even though they occur in plasma only at nanomolar concentrations, they reliably distinguish patients who take metformin regularly from those who take it irregularly or not at all,” emphasizes T. Čajka.<h4>Metabolomics in practice and international collaboration</h4>The study also provides a detailed description of broader metabolic changes in type 2 diabetes, including increases in lactate, organic acids, and branched-chain amino acids, as well as extensive remodelling of the lipid profile. In addition to T. Čajka’s team, collaborators from the Institute for Clinical and Experimental Medicine in Prague and the West Coast Metabolomics Center (University of California, Davis) also participated in the study.The results demonstrate that advanced metabolomics approaches developed at IPHYS within the CarDia project can find highly practical applications both in clinical studies and in personalized monitoring of treatment in patients with diabetes.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://ascpt.onlinelibrary.wiley.com/doi/10.1002/cpt.70205">Untargeted Metabolomics Identifies N-Lactoyl-Amino Acids as Dose-Responsive Plasma Biomarkers of Metformin Adherence in Type 2 Diabetes</a></h4>Tomas Cajka, Jiri Hricko, Lucie Rudl Kulhava, Michaela Paucova, Michaela Novakova, Veronika Hola, Stanislava Rakusanova, Oliver Fiehn, Vojtech Skop, Ivana Lankova, Iva Miskova, Terezie Pelikanova, Martin HaluzikClin Pharmacol Ther, 119: 1057-1069<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1002/cpt.70205">https://doi.org/10.1002/cpt.70205</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>Metformin is the most widely prescribed antidiabetic drug, yet adherence remains difficult to objectively assess. Using untargeted metabolomics and lipidomics, we analyzed plasma from 637 patients with type 2 diabetes (T2D) with confirmed metformin use and 143 nondiabetic controls, annotating 614 metabolites. Patients were stratified by plasma metformin into sub-therapeutic, therapeutic, and supra-therapeutic groups, and associations were evaluated by multiple linear regression and composite metabolite ranking. Five previously unannotated features were structurally identified as N-lactoyl-amino acids, whose levels correlated strongly with plasma metformin (ρ = 0.42–0.55, P &lt; 0.0001) and increased up to 7.2-fold in the supra-therapeutic group (&gt; 2000 ng/mL). While N-lactoyl-amino acids were consistently detected in the nanomolar range, they still displayed robust and dose-dependent associations with metformin. Broader metabolic changes in T2D included elevated lactate, organic acids, and branched-chain amino acids, together with reduced urea cycle metabolites. Lipidomics showed increases in saturated triacylglycerols and diacylglycerols and decreases in cholesteryl esters, sphingomyelins, and phospholipids. These findings establish N-lactoyl-amino acids as robust, dose-responsive plasma biomarkers of metformin exposure. Despite being up to four orders of magnitude less abundant than their amino acid precursors, they sensitively reflect mitochondrial lactate overflow and pharmacodynamic adaptation, offering objective assessment of adherence.

New blood biomarkers reveal how faithfully diabetes patients take metformin

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The Czech Academy of Sciences (CAS) was established by Act No. 283/1992 Coll. as the Czech successor of the former Czechoslovak Academy of Sciences. It is set up as a complex of 54 public research institutions.

Czech Academy of Sciences

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

Organomation, founded in 1959, designs and manufactures high-quality nitrogen evaporators and extraction systems. Known for innovation and durability, their lab instruments are used globally for efficient sample preparation with strong customer support.

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KNAUER Eurospher II Chiral AM Columns for NP & RP (USP L51)

Eurospher II Chiral AM uses the chiral selector Amylose-tris-(3,5 dimethylphenylcarbamate) and is equivalent to Chiralpak AD. 

Eurospher II Chiral AM uses the chiral selector Amylose-tris-(3,5 dimethylphenylcarbamate) and is equivalent to Chiralpak AD. KNAUER offers 2 different CPS versions: Eurospher II Chiral AM is designed for separations in normal phase (NP) mode and Eurospher II Chiral AM-R &nbsp;for separations in reversed phase (RP) mode.<h5>Properties</h5><ul><li>Silica gel: ultra pure, &gt; 99.99 %</li><li>Metal content: &lt; 10 ppm</li><li>Particle size: 3 μm, 5 μm, 10 μm</li><li>Particle form: spherical</li><li>Pore size of base material: 1000 Å</li><li>Chiral selector: Amylose-tris-(3,5-dimethylphenylcarbamate) for Chiral AM&nbsp;</li></ul><h5>Key features</h5><ul><li>KNAUER offers these chiral stationary phases for two different separation modes: Eurospher II Chiral AM is designed for separations in normal phase (NP) mode, Eurospher II Chiral AM-R for separations in reversed phase mode.</li></ul><h5>Recommended application areas</h5><ul><li>Eurospher II Chiral AM columns are able to separate neutral, acidic and basic racemates.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Chiral_AM_906d13b0b5.webp" alt="KNAUER: Eurospher II Chiral AM" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Chiral_AM_906d13b0b5.webp 245w," sizes="100vw" width="690" height="388"><blockquote>Stationary phase Eurospher II Chiral AM (AM-R) is provided in these column types: analytical, semi-preparative and preparative.</blockquote>Eurospher II Chiral AM and AM-R Analytical Columns are available with these parameters:<ul><li>Column length (mm): 50, 100, 150, 250</li><li>Column ID (mm): 4, 4.6</li><li>Particle size (µm): 3, 5, 10</li></ul>Eurospher II Chiral AM and AM-R Semi-Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 150, 250</li><li>Column ID (mm): 10</li><li>Particle size (µm): 5, 10</li></ul><h3>KNAUER Chiral HPLC Columns</h3>For analytical, preparative and SMB chiral separations<ul><li>Column Brand<ul><li>Eurospher II</li></ul></li><li>Reversed Phase Modifications<ul><li>Chiral NR-R</li><li>Chiral AM-R</li><li>Chiral OM-R</li></ul></li><li>Normal Phase Modifications<ul><li>Chiral NR</li><li>Chiral AM</li><li>Chiral OM</li></ul></li><li>Flexibility: Wide selection of column and particle sizes, for preparative and analytical applications</li><li>Expandable: Upscaling even for continuous SMB</li><li>Application Service: We offer a customized screening service for your analytes. You will receive an optimal column recommendation including the method parameters.</li></ul><h4>Eurospher II Chiral</h4>Based on ultra-high purity silica, the Eurospher II chiral column materials are characterized by high enantioselectivity and loadability.&nbsp;Available in a wide range of dimensions for analytical, preparative and SMB (simulated moving bed) applications, Eurospher II Chiral columns are the perfect choice for even the most challenging enantioseparation tasks&nbsp;Since chiral separations are not very well predictable, KNAUER offers a chiral screening service for your samples (Article number: AL0220).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurospher_II_chiral_48c53afebe.jpg" alt="KNAUER: Eurospher II chiral" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurospher_II_chiral_48c53afebe.jpg 245w," sizes="100vw" width="1369" height="633"><blockquote>Tip: Some of the most popular eluents for HPLC (such as acetone, chloroform, DMF, DMSO, MEK, toluene, dioxane, ethyl acetate, methylene chloride, pyridine and THF) which may be remaining in your HPLC system, can destroy Eurospher II Chiral AM and OM phases even in small concentrations! It is highly recommended that the HPLC system is flushed with appropriate eluents before the installation of the chiral column.</blockquote>

KNAUER Eurospher II Chiral OM Columns for NP & RP (USP L40, USP L93)

Eurospher II Chiral OM uses the chiral selector Cellulose-tris-(3,5-dimethylphenylcarbamate) and is equivalent to Chiralcel OD. 

Eurospher II Chiral OM uses the chiral selector Cellulose-tris-(3,5-dimethylphenylcarbamate) and is equivalent to Chiralcel OD. KNAUER offers 2 different CPS versions: Eurospher II Chiral OM is designed for separations in normal phase (NP) mode and Eurospher II Chiral OM-R for separations in reversed phase (RP) mode.<h5>Properties</h5><ul><li>Silica gel: ultra pure, &gt; 99.99 %</li><li>Metal content: &lt; 10 ppm</li><li>Particle size: 3 μm, 5 μm, 10 μm</li><li>Particle form: spherical</li><li>Pore size of base material: 1000 Å</li><li>Chiral selector: Cellulose-tris-(3,5-dimethyl- phenylcarbamate) for Chiral OM</li></ul><h5>Key features</h5><ul><li>KNAUER offers these chiral stationary phases for two different separation modes: Eurospher II Chiral OM is designed for separations in normal phase (NP) mode, Eurospher II Chiral OM-R for separations in reversed phase mode.</li></ul><h5>Recommended application areas</h5><ul><li>Eurospher II Chiral OM columns are able to separate neutral, acidic and basic racemates.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Chiral_OM_c2a3f1a159.webp" alt="KNAUER: Eurospher II Chiral OM" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Chiral_OM_c2a3f1a159.webp 245w," sizes="100vw" width="690" height="388"><blockquote>Stationary phase Eurospher II Chiral OM (OM-R) is provided in these column types: analytical, semi-preparative and preparative.</blockquote>Eurospher II Chiral OM and OM-R Analytical Columns are available with these parameters:<ul><li>Column length (mm): 50, 100, 150, 250</li><li>Column ID (mm): 4, 4.6</li><li>Particle size (µm): 3, 5, 10</li></ul>Eurospher II Chiral OM and OM-R Semi-Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 150, 250</li><li>Column ID (mm): 10</li><li>Particle size (µm): 5, 10</li></ul><h3>KNAUER Chiral HPLC Columns</h3>For analytical, preparative and SMB chiral separations<ul><li>Column Brand<ul><li>Eurospher II</li></ul></li><li>Reversed Phase Modifications<ul><li>Chiral NR-R</li><li>Chiral AM-R</li><li>Chiral OM-R</li></ul></li><li>Normal Phase Modifications<ul><li>Chiral NR</li><li>Chiral AM</li><li>Chiral OM</li></ul></li><li>Flexibility: Wide selection of column and particle sizes, for preparative and analytical applications</li><li>Expandable: Upscaling even for continuous SMB</li><li>Application Service: We offer a customized screening service for your analytes. You will receive an optimal column recommendation including the method parameters.</li></ul><h4>Eurospher II Chiral</h4>Based on ultra-high purity silica, the Eurospher II chiral column materials are characterized by high enantioselectivity and loadability.&nbsp;Available in a wide range of dimensions for analytical, preparative and SMB (simulated moving bed) applications, Eurospher II Chiral columns are the perfect choice for even the most challenging enantioseparation tasks&nbsp;Since chiral separations are not very well predictable, KNAUER offers a chiral screening service for your samples (Article number: AL0220).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurospher_II_chiral_48c53afebe.jpg" alt="KNAUER: Eurospher II chiral" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurospher_II_chiral_48c53afebe.jpg 245w," sizes="100vw" width="1369" height="633"><blockquote>Tip: Some of the most popular eluents for HPLC (such as acetone, chloroform, DMF, DMSO, MEK, toluene, dioxane, ethyl acetate, methylene chloride, pyridine and THF) which may be remaining in your HPLC system, can destroy Eurospher II Chiral AM and OM phases even in small concentrations! It is highly recommended that the HPLC system is flushed with appropriate eluents before the installation of the chiral column.</blockquote>

KNAUER Eurospher II Chiral NR Columns for NP & RP

Eurospher II Chiral NR is an immobilized brush-type phase with very broad generality and orhogonal selectivity to Eurospher II Chiral AM and OM.

Eurospher II Chiral NR is an immobilized brush-type phase with very broad generality and orhogonal selectivity to Eurospher II Chiral AM and OM. In many cases it is much more stable compared to Eurospher II Chiral AM or OM. The Chiral-NR selector is covalently bound, so that you can use all HPLC-eluents.Due to its high loadability it is perfectly suited for preparative separations. Both phases can be used in RP and NP mode. Eurospher II Chiral-NR-R shows reversed elution order compared to Eurospher II Chiral-NR caused by the modification with the opposite enantiomeric form of the chiral selector.<h5>Properties</h5><ul><li>Silica gel: ultra pure, &gt; 99.99 %</li><li>Metal content: &lt; 10 ppm</li><li>Particle size:&nbsp;<ul><li>Eurospher II Chiral NR: 3 μm, 5 μm, 8 µm, 12 µm</li><li>Eurospher II Chiral NR-R: 8 µm, 12 µm</li></ul></li><li>Particle form: spherical</li><li>Pore size of base material: 1000 Å</li></ul><h5>Recommended application areas</h5><ul><li>Eurospher II Chiral NR columns are able to separate analytes with an oxygen at or near the chiral center and additionally an aromatic ring.</li></ul><blockquote>Stationary phase Eurospher II Chiral NR (NR-R) is provided in these column types: analytical, semi-preparative and preparative.</blockquote>Eurospher II Chiral NR and NR-R Analytical Columns are available with these parameters:<ul><li>Column length (mm): 50, 100, 150, 250</li><li>Column ID (mm): 3, 4, 4.6</li><li>Particle size (µm): 3, 5, 8, 12</li></ul>Eurospher II Chiral NR and NR-R Semi-Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 150, 250</li><li>Column ID (mm): 8, 10</li><li>Particle size (µm): 8, 12</li></ul><h3>KNAUER Chiral HPLC Columns</h3>For analytical, preparative and SMB chiral separations<ul><li>Column Brand<ul><li>Eurospher II</li></ul></li><li>Reversed Phase Modifications<ul><li>Chiral NR-R</li><li>Chiral AM-R</li><li>Chiral OM-R</li></ul></li><li>Normal Phase Modifications<ul><li>Chiral NR</li><li>Chiral AM</li><li>Chiral OM</li></ul></li><li>Flexibility: Wide selection of column and particle sizes, for preparative and analytical applications</li><li>Expandable: Upscaling even for continuous SMB</li><li>Application Service: We offer a customized screening service for your analytes. You will receive an optimal column recommendation including the method parameters.</li></ul><h4>Eurospher II Chiral</h4>Based on ultra-high purity silica, the Eurospher II chiral column materials are characterized by high enantioselectivity and loadability.&nbsp;Available in a wide range of dimensions for analytical, preparative and SMB (simulated moving bed) applications, Eurospher II Chiral columns are the perfect choice for even the most challenging enantioseparation tasks&nbsp;Since chiral separations are not very well predictable, KNAUER offers a chiral screening service for your samples (Article number: AL0220).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurospher_II_chiral_48c53afebe.jpg" alt="KNAUER: Eurospher II chiral" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurospher_II_chiral_48c53afebe.jpg 245w," sizes="100vw" width="1369" height="633"><blockquote>Tip: Some of the most popular eluents for HPLC (such as acetone, chloroform, DMF, DMSO, MEK, toluene, dioxane, ethyl acetate, methylene chloride, pyridine and THF) which may be remaining in your HPLC system, can destroy Eurospher II Chiral AM and OM phases even in small concentrations! It is highly recommended that the HPLC system is flushed with appropriate eluents before the installation of the chiral column.</blockquote>

KNAUER Eurokat H Ion Exclusion/Ligand Exchange Columns (USP L17)

The Eurokat H ionic form is especially designed for the analysis of organic acids and even complex mixtures of acids, sugars and alcohols as well as sugar alcohols.

Organic acids and alcoholsThe Eurokat H ionic form is especially designed for the analysis of organic acids and even complex mixtures of acids, sugars and alcohols as well as sugar alcohols. It is a cation exchange material with 8 % cross linkage of the styrenedivinylbenzene copolymer. Best results are acieved with aqueous eluents and small amounts of anorganic acids, recommended eluent 0.005 M sulfuric acid. The usage of up to 10 % organic content in the mobile phase is possible.<h5>Properties</h5><ul><li>Sulfonated cross-linked styrenedivinylbenzene copolymer phase for the determination of organic acids, carbohydrates and alcohols</li><li>H-form, 8 % cross linkage</li><li>Cation exchanger, extremly long lasting lifetime when correctly handled, best results with aqueous eluents and small amounts of anorganic acids, recommended eluent 0,01 N sulfuric acid, usage of up to 10 % organic content in the mobile phase is possible</li></ul><h5>Technical Data</h5><ul><li>Sulfonated cross-linked styrenedivinylbenzene copolymer with 8 % cross linkage in the ionic form H, available in 10 μm particle size, pressure stable up to maximum 100 bar</li></ul><h5>Recommended application areas</h5><ul><li>Eurokat H is especially designed for the analysis of organic acids and even complex mixtures of acids, sugars and alcohols as well as sugar alcohols. Due to a differing separation process we recommend the use of these type of columns only in 8 mm ID or 4 mm ID.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurokat_H_Chromatogram_e2c6665a1f.webp" alt="KNAUER: Eurokat H Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurokat_H_Chromatogram_e2c6665a1f.webp 245w," sizes="100vw" width="690" height="281"><blockquote>Tip: Eurokat columns are characterized by an extremely long lifetime if handled properly. Especially pressure shocks and organic solvent contents of more than 10 % in the mobile phase should be avoided absolutely.</blockquote><h3>KNAUER Ion Exclusion and Ligand Exchange Columns</h3>Separation of organic acids, carbohydrates, alcohols on sulfonated cross-linked styrenedivinylbenzene copolymer<ul><li>Modifications<ul><li>Eurokat H</li><li>Eurokat Ca</li><li>Eurokat Pb</li><li>Eurokat Na</li></ul></li><li>High Temperature Methods: Up to 90 °C</li><li>Method Development: Optional up to 10 % organic solvent</li><li>Chemically stable: pH 1–12</li><li>Sustainability: Aqueous eluents protect the environment and are cost-effectiv</li><li>User Friendly: Simple and robust methods for daily analysis. Versatile in its use.</li><li>Simplicity: Easy purchase via our online store with fast delivery.&nbsp;</li></ul><h4>Characteristics&nbsp;</h4>Eurokat high performance polymer phases were especially developed for the separation of organic acids, carbohydrates, alcohols and even complex mixtures of these compounds. Eurokat is a sulfonated cross-linked styrenedivinylbenzene copolymer available in several ionic forms (H, Ca and Pb). This particular cation exchanger is characterized by an outstanding density of functional groups, making it the ideal choice for your ion exclusion, size exclusion and ligand exchange chromatography.<h4>Choice of chromatographic conditions&nbsp;</h4>The Eurokat stationary phase is designed to be applicable to a wide range of diverse chromatographic conditions. All Eurokat columns can be used at temperatures up to 90 °C with no organic solvents. The best separation of sugars can be achieved using between 60 to 90 °C. To extend separation performance, it is possible to connect up to three columns of Eurokat in series. Eurokat columns require no organic solvents and thus are environmentally friendly.&nbsp;<h4>Stability&nbsp;</h4>Eurokat polymer columns are extremely stable over the whole pH range. This is one striking advantage compared with silica-based phases which have a limited lifetime at pH extremes, especially in the higher pH range. Most importantly, Eurokat phases show extraordinary column lifetime stability and are not affected by aqueous solvents.&nbsp;<h4>Application areas&nbsp;</h4><ul><li>Carbohydrates and organic acids in softdrinks and fruit juices&nbsp;</li><li>Sugar substitutes</li><li>Food preservatives</li><li>Dairy products</li><li>Urine analytic (Uric acid, Hippuric acid)</li><li>Monitoring of fermentation processes</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg" alt="KNAUER: Eurokat - Principle of ligand exchange mechanism" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg 245w," sizes="100vw" width="1382" height="570">

KNAUER Eurokat Pb & Ca Ion Exclusion/Ligand Exchange Columns (USP L34 / USP L19)

The ionic forms Ca and Pb are best suited for the analysis of smaller carbohydrates like mono- and disaccharides and sugars up to a degree of polymerization (DP) of 4. 

Analysis of mono- and disaccharidesThe ionic forms Ca and Pb are best suited for the analysis of smaller carbohydrates like mono- and disaccharides and sugars up to a degree of polymerization (DP) of 4. It is a cation exchange material with 6 % cross linkage of the styrenedivinylbenzene copolymer. Best results are achieved with aqueous eluents, recommended eluent is pure deionized water. The usage of up to 10 % organic content in the mobile phase is possible.<h5>Properties</h5><ul><li>Polymer phase for the determination of mono- and disaccharides</li><li>Pb (USP L34) form, 6 % cross linkage</li><li>Cation exchanger, extremely long lasting lifetime when correctly handled, best results with aqueous eluents, recommended eluent is pure deionized water, usage of up to 10 % organic content in the mobile phase is possible</li></ul><h5>Technical Data</h5><ul><li>Sulfonated cross-linked styrenedivinylbenzene copolymer with 6 % cross linkage in the ionic form Pb, available in 10μm particle size, pressure stable up to maximum 100 bar</li></ul><h5>Recommended application areas</h5><ul><li>Especially designed for the analysis of small carbohydrates up to DP 4</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurokat_Pb_Ca_Chromatogram_2054f70e49.webp" alt="KNAUER: Eurokat Pb &amp; Ca Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurokat_Pb_Ca_Chromatogram_2054f70e49.webp 245w," sizes="100vw" width="690" height="271"><blockquote>Tip: Eurokat columns are used at high temperatures. During equilibration it is very important to have an eye on the backpressure and to start with very low flow rates and increase them only slowly and stepwise after the column has adapted to the temperature.</blockquote><h3>KNAUER Ion Exclusion and Ligand Exchange Columns</h3>Separation of organic acids, carbohydrates, alcohols on sulfonated cross-linked styrenedivinylbenzene copolymer<ul><li>Modifications<ul><li>Eurokat H</li><li>Eurokat Ca</li><li>Eurokat Pb</li><li>Eurokat Na</li></ul></li><li>High Temperature Methods: Up to 90 °C</li><li>Method Development: Optional up to 10 % organic solvent</li><li>Chemically stable: pH 1–12</li><li>Sustainability: Aqueous eluents protect the environment and are cost-effectiv</li><li>User Friendly: Simple and robust methods for daily analysis. Versatile in its use.</li><li>Simplicity: Easy purchase via our online store with fast delivery.&nbsp;</li></ul><h4>Characteristics&nbsp;</h4>Eurokat high performance polymer phases were especially developed for the separation of organic acids, carbohydrates, alcohols and even complex mixtures of these compounds. Eurokat is a sulfonated cross-linked styrenedivinylbenzene copolymer available in several ionic forms (H, Ca and Pb). This particular cation exchanger is characterized by an outstanding density of functional groups, making it the ideal choice for your ion exclusion, size exclusion and ligand exchange chromatography.<h4>Choice of chromatographic conditions&nbsp;</h4>The Eurokat stationary phase is designed to be applicable to a wide range of diverse chromatographic conditions. All Eurokat columns can be used at temperatures up to 90 °C with no organic solvents. The best separation of sugars can be achieved using between 60 to 90 °C. To extend separation performance, it is possible to connect up to three columns of Eurokat in series. Eurokat columns require no organic solvents and thus are environmentally friendly.&nbsp;<h4>Stability&nbsp;</h4>Eurokat polymer columns are extremely stable over the whole pH range. This is one striking advantage compared with silica-based phases which have a limited lifetime at pH extremes, especially in the higher pH range. Most importantly, Eurokat phases show extraordinary column lifetime stability and are not affected by aqueous solvents.&nbsp;<h4>Application areas&nbsp;</h4><ul><li>Carbohydrates and organic acids in softdrinks and fruit juices&nbsp;</li><li>Sugar substitutes</li><li>Food preservatives</li><li>Dairy products</li><li>Urine analytic (Uric acid, Hippuric acid)</li><li>Monitoring of fermentation processes</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg" alt="KNAUER: Eurokat - Principle of ligand exchange mechanism" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg 245w," sizes="100vw" width="1382" height="570">

KNAUER Eurokat Na Ion Exclusion/Ligand Exchange Columns

The ionic form Na is best suited for the analysis of sugars oligomers up to a degree of polymerization (DP) of 8. 

Analysis of sugar oligomersThe ionic form Na is best suited for the analysis of sugars oligomers up to a degree of polymerization (DP) of 8. It is a cation exchange material with 6 % cross linkage of the styrenedivinylbenzene copolymer. Best results are achieved with aqueous eluents, recommended eluent is pure deionized water. The usage of up to 10 % organic content in the mobile phase is possible.&nbsp;<h5>Properties</h5><ul><li>Polymer phase for the determination of sugar oligomers</li><li>Na form, 6 % cross linkage</li><li>Cation exchanger, extremly long lasting lifetime when correctly handled, best results with aqueous eluents, recommended eluent is pure deionized water, usage of up to 10 % organic content in the mobile phase is possible</li></ul><h5>Technical Data</h5><ul><li>Sulfonated cross-linked styrenedivinylbenzene copolymer with 6 % cross linkage in the ionic form Na, available in 10 μm particle size, pressure stable up to maximum 100 bar</li></ul><h5>Recommended application areas</h5><ul><li>Especially designed for the analysis of sugar oligomers, separates carbohydrates up to DP 8</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurokat_Na_Chromatogram_7d3d81fa52.webp" alt="KNAUER: Eurokat Na Chromatogram" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurokat_Na_Chromatogram_7d3d81fa52.webp 188w," sizes="100vw" width="686" height="568"><blockquote>Tip: Eurokat columns are typically used with 100 % aqueous eluents. For storage, please avoid microbial growth by flushing the Eurokat column with 0.45 µm filtered ultrapure water and storing it at 4 °C.</blockquote><h3>KNAUER Ion Exclusion and Ligand Exchange Columns</h3>Separation of organic acids, carbohydrates, alcohols on sulfonated cross-linked styrenedivinylbenzene copolymer<ul><li>Modifications<ul><li>Eurokat H</li><li>Eurokat Ca</li><li>Eurokat Pb</li><li>Eurokat Na</li></ul></li><li>High Temperature Methods: Up to 90 °C</li><li>Method Development: Optional up to 10 % organic solvent</li><li>Chemically stable: pH 1–12</li><li>Sustainability: Aqueous eluents protect the environment and are cost-effectiv</li><li>User Friendly: Simple and robust methods for daily analysis. Versatile in its use.</li><li>Simplicity: Easy purchase via our online store with fast delivery.&nbsp;</li></ul><h4>Characteristics&nbsp;</h4>Eurokat high performance polymer phases were especially developed for the separation of organic acids, carbohydrates, alcohols and even complex mixtures of these compounds. Eurokat is a sulfonated cross-linked styrenedivinylbenzene copolymer available in several ionic forms (H, Ca and Pb). This particular cation exchanger is characterized by an outstanding density of functional groups, making it the ideal choice for your ion exclusion, size exclusion and ligand exchange chromatography.<h4>Choice of chromatographic conditions&nbsp;</h4>The Eurokat stationary phase is designed to be applicable to a wide range of diverse chromatographic conditions. All Eurokat columns can be used at temperatures up to 90 °C with no organic solvents. The best separation of sugars can be achieved using between 60 to 90 °C. To extend separation performance, it is possible to connect up to three columns of Eurokat in series. Eurokat columns require no organic solvents and thus are environmentally friendly.&nbsp;<h4>Stability&nbsp;</h4>Eurokat polymer columns are extremely stable over the whole pH range. This is one striking advantage compared with silica-based phases which have a limited lifetime at pH extremes, especially in the higher pH range. Most importantly, Eurokat phases show extraordinary column lifetime stability and are not affected by aqueous solvents.&nbsp;<h4>Application areas&nbsp;</h4><ul><li>Carbohydrates and organic acids in softdrinks and fruit juices&nbsp;</li><li>Sugar substitutes</li><li>Food preservatives</li><li>Dairy products</li><li>Urine analytic (Uric acid, Hippuric acid)</li><li>Monitoring of fermentation processes</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg" alt="KNAUER: Eurokat - Principle of ligand exchange mechanism" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Principle_of_ligand_exchange_mechanism_a5b7c21c43.jpg 245w," sizes="100vw" width="1382" height="570">

KNAUER Eurosil Bioselect 300 C4 HPLC Columns (USP L26)

Eurosil Bioselect C4 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weight of approximately 100 kDa. 

Analytical wide pore phase for the determination of biomolecules bigger than 20 kDaEurosil Bioselect C4 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weight of approximately 100 kDa. The optimized manufacturing process guarantees excellent batch–to-batch reproducibility. The Eurosil Bioselect sorbent is the first choice for Biochromatography with silica material.<h5>Properties</h5><ul><li>Ultra pure, spherical wide pore HPLC phase based on wide pore silica gel</li><li>Unpolar, monomeric C4 modification, endcapped</li><li>2 % carbon content (conventional endcapping)</li><li>Separation mechanism: hydrophobic and hydrophilic interaction</li></ul><figure class="image"><img style="aspect-ratio:200/400;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C4_3f3adfbdb4.webp" alt="KNAUER: C4" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C4_3f3adfbdb4.webp 78w," sizes="100vw" width="200" height="400"></figure><h5>Recommended application areas</h5><ul><li>Hydrophilic biomolecules and especially peptides larger than 10 000- 20 000 Da</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg" alt="KNAUER: Eurosil Bioselect - Phases and recommended sizes of molecules" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg 245w," sizes="100vw" width="1385" height="778"><h3>KNAUER Wide pore HPLC columns</h3>For enhanced resolution, capacity and recovery of proteins and other biomolecules<ul><li>Material: Silica or polymer particles</li><li>Separation Ranges: 2–100 kDa</li><li>Column Brands: Eurosil Bioselect or AppliChrom®</li><li>Particle sizes: 3–10 µm</li><li>Pore Sizes: 300 or 100–1000 Å</li><li>Specific surface: 90 ± 5 m2/g</li><li>Pore volume: 0.8 ml/g</li><li>Density: 450 g/l</li><li>Applications: Peptides exceeding approximately 50 amino acids and oligonucleotides greater than 25 residues</li><li>Customize: Bioanalysis requires a lot of flexibility in the pore size, the pH range, the temperatures and the solvents used. To achieve this, we cross phase limits.</li></ul><h4>Characteristics&nbsp;</h4><ul><li>Eurosil Bioselect columns are available in 4 modifications, useful for a wide range of separation tasks involving large molecules up to 100 000 Da.</li><li>Strict manufacturing procedures ensure a very narrow pore size distribution.</li><li>Interfering anions or heavy metal ions on the silica surface are not present in Eurosil Bioselect columns because only ultra pure silica gel and high quality chemical modifications are employed.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_85cfc2d201.jpg" alt="KNAUER: Eurosil Bioselect" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_85cfc2d201.jpg 222w," sizes="100vw" width="1114" height="782"><h4>Separation mechanism of Eurosil Bioselect</h4>To separate larger molecules, they need to freely access the interior of the pores of the packing material. Therefore, the analytes’ diameter must be smaller than the average pore diameter.&nbsp;For higher molecular weight solutes, the use of lower pore size materials (60-120 Å) as typically used for the analysis of small molecules may result restricted diffusion in the material´s pores and therewith reduced column efficiency.&nbsp;<h4>Modifications</h4>The recommended modification of Eurosil Bioselect depends on the molecular weight of the analytes.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg" alt="KNAUER: Eurosil Bioselect - chemical modifications" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg 245w," sizes="100vw" width="955" height="505"> &nbsp;

KNAUER Eurosil Bioselect 300 C8 HPLC Columns (USP L7)

Eurosil Bioselect C8 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weight of approximately 20 kDa.

Analytical wide pore phase for the determination of biomolecules bigger than 5000 DaEurosil Bioselect C8 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weight of approximately 20 kDa.<h5>Properties</h5><ul><li>Ultra pure, spherical wide pore HPLC phase based on wide pore silica gel</li><li>Unpolar, monomeric C8 modification, endcapped</li><li>4.5 % carbon content (conventional endcapping)</li><li>Separation mechanism: hydrophobic interaction</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C8_hydrosphob_6986c292b4.webp" alt="KNAUER: C8" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C8_hydrosphob_6986c292b4.webp 144w," sizes="100vw" width="381" height="413"><h5>Recommended application areas</h5><ul><li>Hydrophilic biomolecules, peptides, peptide mapping after enzymatic digestion</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg" alt="KNAUER: Eurosil Bioselect - Phases and recommended sizes of molecules" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg 245w," sizes="100vw" width="1385" height="778"><h3>KNAUER Wide pore HPLC columns</h3>For enhanced resolution, capacity and recovery of proteins and other biomolecules<ul><li>Material: Silica or polymer particles</li><li>Separation Ranges: 2–100 kDa</li><li>Column Brands: Eurosil Bioselect or AppliChrom®</li><li>Particle sizes: 3–10 µm</li><li>Pore Sizes: 300 or 100–1000 Å</li><li>Specific surface: 90 ± 5 m2/g</li><li>Pore volume: 0.8 ml/g</li><li>Density: 450 g/l</li><li>Applications: Peptides exceeding approximately 50 amino acids and oligonucleotides greater than 25 residues</li><li>Customize: Bioanalysis requires a lot of flexibility in the pore size, the pH range, the temperatures and the solvents used. To achieve this, we cross phase limits.</li></ul><h4>Characteristics&nbsp;</h4><ul><li>Eurosil Bioselect columns are available in 4 modifications, useful for a wide range of separation tasks involving large molecules up to 100 000 Da.</li><li>Strict manufacturing procedures ensure a very narrow pore size distribution.</li><li>Interfering anions or heavy metal ions on the silica surface are not present in Eurosil Bioselect columns because only ultra pure silica gel and high quality chemical modifications are employed.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_85cfc2d201.jpg" alt="KNAUER: Eurosil Bioselect" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_85cfc2d201.jpg 222w," sizes="100vw" width="1114" height="782"><h4>Separation mechanism of Eurosil Bioselect</h4>To separate larger molecules, they need to freely access the interior of the pores of the packing material. Therefore, the analytes’ diameter must be smaller than the average pore diameter.&nbsp;For higher molecular weight solutes, the use of lower pore size materials (60-120 Å) as typically used for the analysis of small molecules may result restricted diffusion in the material´s pores and therewith reduced column efficiency.&nbsp;<h4>Modifications</h4>The recommended modification of Eurosil Bioselect depends on the molecular weight of the analytes.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg" alt="KNAUER: Eurosil Bioselect - chemical modifications" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg 245w," sizes="100vw" width="955" height="505"> &nbsp;

KNAUER Eurosil Bioselect 300 C18 HPLC Columns (USP L1)

Eurosil Bioselect C18 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weigth of approximately 5 kDa.

Analytical wide pore phase for the determination of biomolecules bigger than 2000 Da​Eurosil Bioselect C18 has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weigth of approximately 5 kDa.<h5>Properties</h5><ul><li>Ultra pure, spherical wide pore HPLC phase based on silica gel</li><li>Unpolar, monomeric C18 (Octadecyl) modification, endcapped</li><li>7.5 % carbon content (conventional endcapping)</li><li>Separation mechanism: hydrophobic interaction</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C18_Endcapped_standard_edd2523aca.webp" alt="KNAUER: C18 Endcapped standard" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C18_Endcapped_standard_edd2523aca.webp 234w," sizes="100vw" width="688" height="458"><h5>Recommended application areas</h5><ul><li>Hydrophilic biomolecules, peptides, peptide mapping after enzymatic digestion</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg" alt="KNAUER: Eurosil Bioselect - Phases and recommended sizes of molecules" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg 245w," sizes="100vw" width="1385" height="778"><blockquote>Tip: Caused by the larger pore size of 300 Å, Eurosil Bioselect phases are not as mechanical stable as classical silica gel phases with up to 150 Å and should not be used above 200 bar pressure.</blockquote><h3>KNAUER Wide pore HPLC columns</h3>For enhanced resolution, capacity and recovery of proteins and other biomolecules<ul><li>Material: Silica or polymer particles</li><li>Separation Ranges: 2–100 kDa</li><li>Column Brands: Eurosil Bioselect or AppliChrom®</li><li>Particle sizes: 3–10 µm</li><li>Pore Sizes: 300 or 100–1000 Å</li><li>Specific surface: 90 ± 5 m2/g</li><li>Pore volume: 0.8 ml/g</li><li>Density: 450 g/l</li><li>Applications: Peptides exceeding approximately 50 amino acids and oligonucleotides greater than 25 residues</li><li>Customize: Bioanalysis requires a lot of flexibility in the pore size, the pH range, the temperatures and the solvents used. To achieve this, we cross phase limits.</li></ul><h4>Characteristics&nbsp;</h4><ul><li>Eurosil Bioselect columns are available in 4 modifications, useful for a wide range of separation tasks involving large molecules up to 100 000 Da.</li><li>Strict manufacturing procedures ensure a very narrow pore size distribution.</li><li>Interfering anions or heavy metal ions on the silica surface are not present in Eurosil Bioselect columns because only ultra pure silica gel and high quality chemical modifications are employed.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_85cfc2d201.jpg" alt="KNAUER: Eurosil Bioselect" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_85cfc2d201.jpg 222w," sizes="100vw" width="1114" height="782"><h4>Separation mechanism of Eurosil Bioselect</h4>To separate larger molecules, they need to freely access the interior of the pores of the packing material. Therefore, the analytes’ diameter must be smaller than the average pore diameter.&nbsp;For higher molecular weight solutes, the use of lower pore size materials (60-120 Å) as typically used for the analysis of small molecules may result restricted diffusion in the material´s pores and therewith reduced column efficiency.&nbsp;<h4>Modifications</h4>The recommended modification of Eurosil Bioselect depends on the molecular weight of the analytes.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg" alt="KNAUER: Eurosil Bioselect - chemical modifications" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg 245w," sizes="100vw" width="955" height="505"> &nbsp;

KNAUER Eurosil Bioselect 300 C18A HPLC Columns (USP L1)

Eurosil Bioselect C18A has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weigth of approximately 5 kDa.

Analytical wide pore phase for the determination of biomolecules up to 5000 Da​Eurosil Bioselect C18A has been specifically developed for the determination and purification of peptides, proteins, and oligonucleotides up to a molecular weigth of approximately 5 kDa.<h5>Properties</h5><ul><li>Ultra pure, spherical wide pore HPLC phase based on silica gel</li><li>Unpolar, monomeric C18 (Octadecyl) modification, endcapped</li><li>7 % carbon content (hydrophilic endcapping)</li><li>Separation mechanism: hydrophobic interaction</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C18_A_6f4b0c3063.webp" alt="KNAUER: C18A" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C18_A_6f4b0c3063.webp 245w," sizes="100vw" width="690" height="428"><h5>Recommended application areas</h5><ul><li>Hydrophilic and polar biomolecules, peptides, very polar biomolecules separated with 100 % aqueous eluents</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg" alt="KNAUER: Eurosil Bioselect - Phases and recommended sizes of molecules" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_Phases_98acc32d0e.jpg 245w," sizes="100vw" width="1385" height="778"><h3>KNAUER Wide pore HPLC columns</h3>For enhanced resolution, capacity and recovery of proteins and other biomolecules<ul><li>Material: Silica or polymer particles</li><li>Separation Ranges: 2–100 kDa</li><li>Column Brands: Eurosil Bioselect or AppliChrom®</li><li>Particle sizes: 3–10 µm</li><li>Pore Sizes: 300 or 100–1000 Å</li><li>Specific surface: 90 ± 5 m2/g</li><li>Pore volume: 0.8 ml/g</li><li>Density: 450 g/l</li><li>Applications: Peptides exceeding approximately 50 amino acids and oligonucleotides greater than 25 residues</li><li>Customize: Bioanalysis requires a lot of flexibility in the pore size, the pH range, the temperatures and the solvents used. To achieve this, we cross phase limits.</li></ul><h4>Characteristics&nbsp;</h4><ul><li>Eurosil Bioselect columns are available in 4 modifications, useful for a wide range of separation tasks involving large molecules up to 100 000 Da.</li><li>Strict manufacturing procedures ensure a very narrow pore size distribution.</li><li>Interfering anions or heavy metal ions on the silica surface are not present in Eurosil Bioselect columns because only ultra pure silica gel and high quality chemical modifications are employed.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_85cfc2d201.jpg" alt="KNAUER: Eurosil Bioselect" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_85cfc2d201.jpg 222w," sizes="100vw" width="1114" height="782"><h4>Separation mechanism of Eurosil Bioselect</h4>To separate larger molecules, they need to freely access the interior of the pores of the packing material. Therefore, the analytes’ diameter must be smaller than the average pore diameter.&nbsp;For higher molecular weight solutes, the use of lower pore size materials (60-120 Å) as typically used for the analysis of small molecules may result restricted diffusion in the material´s pores and therewith reduced column efficiency.&nbsp;<h4>Modifications</h4>The recommended modification of Eurosil Bioselect depends on the molecular weight of the analytes.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg" alt="KNAUER: Eurosil Bioselect - chemical modifications" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Eurosil_Bioselect_chemical_modifications_1fd5d87f7b.jpg 245w," sizes="100vw" width="955" height="505"> &nbsp;

Products from category Analytical HPLC columns focused on Consumables distributed by KNAUER - page 1

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