Join us for a fascinating conversation with Dr. Subhoja Chakraborty from the University of Central Florida, whose cutting-edge research targets the global challenge of malaria drug resistance. Dr. Chakraborty shares her journey from structure-based drug design during her PhD to her recent collaborative work repurposing human kinase inhibitors as rapid, selective antimalarials against drug-resistant Plasmodium falciparum strains.<h4>In this episode, you'll learn:</h4><ul><li>How structure-guided approaches reveal potential drug targets, including cysteine proteases like falcipain-2, and kinases implicated in malaria's complex life cycle.</li><li>The power of repurposing kinase inhibitors originally developed for cancer and other diseases, focusing on compound 12, which blocks hemozoin formation and protein kinase 6—key steps in parasite survival.</li><li>Lab techniques such as affinity, gel filtration, and size exclusion chromatography for recombinant protein purification—and how troubleshooting is crucial for high-yield, stable complexes.</li><li>Advances in mass spectrometry for characterizing protein interactions, validating drug targets, and mapping molecular pathways pivotal to malaria therapeutics.</li><li>Tips and lessons for new researchers facing the challenges of sample preparation, complex protocols, and working as part of a collaborative team.</li></ul>Dr. Chakraborty’s insights bridge the gap between basic science and translational drug discovery, offering hope for more effective, targeted malaria treatments in a world where resistance to frontline therapies threatens millions.<h4>Referenced Papers:</h4><ul><li>"Plasmodium falciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity" (Cell Chemical Biology, 2025)</li><li>"New insights of falcipain 2 structure from Plasmodium falciparum 3D7 strain" (BBRC, 2022)</li><li>"Structure-Based Optimization of Protease−Inhibitor Interactions to Enhance Specificity of Human Stefin‑A against Falcipain‑2 from the Plasmodium falciparum 3D7 Strain" (Biochemistry, 2023)</li></ul>If you’re a student, scientist, or simply passionate about advances in infectious disease research, this episode offers actionable insights, inspiring advice, and a front-row seat to innovation in combating malaria.<h3>Video Transcription</h3><h4>From Structural Biology to Drug Discovery: Chromatography and Mass Spectrometry in Malaria Research</h4><h5>Introduction</h5>In this discussion, Subhoja shares insights into her research journey, focusing on malaria drug discovery and the role of modern analytical techniques in biological and biomedical research. The conversation is aimed primarily at undergraduate students and early-career researchers interested in chemistry, biotechnology, and life sciences.<h5>Research Focus: Malaria Drug Discovery and Kinase Targets</h5>Subhoja is currently involved in malaria drug discovery research at the University of Central Florida, where she has been working since beginning her postdoctoral position two years ago. Her earlier PhD research focused on structure-based drug design in malaria, using a combination of in silico approaches, recombinant protein expression, and X-ray crystallography to determine precise three-dimensional structures of target proteins and their inhibitors.This structural perspective provided a foundation for her current work, which centers on drug discovery through compound screening and repurposing. A recent publication from her laboratory explores the use of repurposed mammalian CDK-like kinase inhibitors as potential antimalarial agents. While such kinase inhibitors are well known in cancer and cardiovascular research, their application to malaria targets represents a novel and promising approach.Kinases are attractive drug targets because of their central role in cell signaling and growth pathways. By targeting specific kinases involved in different stages of the malaria parasite life cycle—whether asexual growth, gametocytogenesis, or differentiation—it may be possible to significantly inhibit parasite growth and progression.<h5>Chromatography in Protein Expression and Purification Workflows</h5>Chromatography plays a critical role throughout Subhoja’s research. Her experience spans from basic chromatography techniques during her early training to advanced protein purification workflows using affinity chromatography, gel filtration (size exclusion chromatography), and ion exchange chromatography.Recombinant proteins are routinely purified using affinity resins such as nickel or cobalt, followed by further purification to remove contaminants. Fast Protein Liquid Chromatography (FPLC) enables compact, stepwise purification workflows suitable for producing proteins for in vitro assays.A recurring challenge in this process is the expression of high-molecular-weight proteins, which often accumulate in insoluble fractions or inclusion bodies. Careful selection of expression vectors, host systems, and induction conditions is therefore essential to maximize yield and solubility.<h5>Integrating Size Exclusion Chromatography into the Workflow</h5>Size exclusion chromatography (SEC) is typically used after affinity purification to further improve protein purity. Following elution with imidazole or glutathione, desalting is required to prevent buffer components from interfering with downstream assays. This is often achieved using desalting columns such as G-25 or PD-10.To remove lower-molecular-weight contaminants, finer SEC media—such as Superdex or Sephacryl columns—are employed. Concentration steps using molecular-weight cut-off filters are then applied to obtain the desired protein concentration for functional studies.These iterative purification and troubleshooting steps are a routine part of protein biochemistry and reflect the importance of methodical optimization and careful validation.<h5>The Role of Mass Spectrometry in Biomolecular Characterization</h5>Mass spectrometry is a key analytical tool in Subhoja’s research pipeline, particularly for target identification and validation. In both malaria and cancer research, MS is used alongside chromatography, immunoprecipitation, and pull-down assays to study protein interactions and molecular recognition events.Affinity-based mass spectrometry enables the identification of binding partners and interactors, whether studying proteins, long non-coding RNAs, or protein complexes. Techniques such as native MS, tandem affinity purification, and proximity labeling (e.g., TurboID-based workflows) provide deeper insights into molecular networks and signaling pathways.These approaches are essential for understanding how candidate drug targets function within complex biological systems.<h5>Sample Preparation Challenges in Biological Research</h5>Sample preparation remains one of the most challenging aspects of biological experimentation. Whole-cell lysates contain proteases, nucleases, and other components that can rapidly degrade target molecules. Preventing degradation requires minimizing preparation time, maintaining low temperatures, and using appropriate inhibitor cocktails.Reproducibility is also critical: biological experiments require multiple replicates, and variability is often unavoidable. Careful handling, protocol optimization, and continuous troubleshooting are essential to ensure reliable results, whether preparing samples for chromatography, mass spectrometry, sequencing, or immunoprecipitation.<h5>Advances in Chromatography and MS for Malaria Research</h5>Modern advances in chromatography and mass spectrometry significantly enhance malaria research by enabling precise target identification, quantification, and functional characterization. Drug discovery workflows begin with construct design and recombinant expression, followed by purification and interaction studies.In malaria research, stage-specific parasite biology requires careful extraction and analysis of proteins from different life cycle stages. Tandem affinity MS, immunoprecipitation, and in vivo validation studies help confirm target relevance and therapeutic potential.Recent work on repurposed kinase inhibitors has shown promising results, including inhibition of hemozoin formation—a key detoxification pathway for the malaria parasite—highlighting the potential of such compounds for further development.<h5>Malaria, Drug Resistance, and Global Impact</h5>Malaria remains a major global health burden, with over 600,000 deaths annually and widespread drug resistance complicating treatment. Artemisinin resistance, particularly associated with mutations in the K13 propeller domain, has driven the search for new targets and therapies.During her PhD, Subhoja focused on falcipain-2, a cysteine protease involved in hemoglobin degradation within the parasite. This pathway is critical for parasite survival and has emerged as a promising drug target. Her work revealed that falcipain-2 operates within a larger protein complex responsible for hemoglobin processing and amino acid release.Understanding these molecular mechanisms is essential for developing robust, stage-specific antimalarial strategies.<h5>Advice for Early-Career Researchers</h5>For researchers just starting out, Subhoja emphasizes the importance of hands-on experience. Working directly with cells, lysates, and analytical tools is essential for truly understanding experimental systems. Failure is an inherent part of research, and perseverance is key.Motivation, teamwork, careful sample handling, and thorough preparation all contribute to long-term success. Reading extensively, critically evaluating one’s own work, and appreciating incremental progress are vital aspects of a sustainable research career.Every successful experiment—no matter how small—represents meaningful progress and contributes to the broader goals of science and medicine.<h5>Closing Remarks</h5>The discussion highlights how interdisciplinary approaches combining chromatography, mass spectrometry, structural biology, and biochemistry are driving advances in malaria drug discovery. Through careful experimental design, analytical rigor, and collaborative teamwork, researchers can address complex biological challenges and contribute to global health solutions.<blockquote>This text has been automatically transcribed from a video presentation using AI technology. It may contain inaccuracies and is not guaranteed to be 100% correct.</blockquote><blockquote><h4>Concentrating on Chromatography Podcast</h4>Dive into the frontiers of chromatography, mass spectrometry, and sample preparation with host David Oliva. Each episode features candid conversations with leading researchers, industry innovators, and passionate scientists who are shaping the future of analytical chemistry. From decoding PFAS detection challenges to exploring the latest in AI-assisted liquid chromatography, this show uncovers practical workflows, sustainability breakthroughs, and the real-world impact of separation science. Whether you’re a chromatographer, lab professional, or researcher you'll discover inspiring content!You can find Concentrating on Chromatography Podcast in podcast apps:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://open.spotify.com/show/1wZg67rCjoGju4yhqxI3tL">Spotify</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podcasts.apple.com/tz/podcast/concentrating-on-chromatography/id1788429185">Apple podcast</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podscan.fm/podcasts/concentrating-on-chromatography">podscan</a></li></ul>and on <a target="_blank" rel="noopener noreferrer" href="https://www.youtube.com/@ChromatographyTalk/videos">YouTube channel</a></blockquote>

Affinity, Gel Filtration, Size Exclusion Chromatography: Repurposing Kinase Inhibitors for Malaria

In the week of February 9, the following webinars await you in the field of liquid phase and especially HPLC and LC/MS.<blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://lcms.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><h5>1. SelectScience: High-Throughput Stability Screening Strategies for Antibody Formulation</h5><ul><li>Tu, 10.2.2026 17:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5807">Registration</a></li></ul>Learn how high-throughput DLS/SLS and rapid-screening DSC accelerate stability assessment of high-concentration antibody formulations, enabling faster, data-driven biologics development.<h5>2. Phenomenex: Big Scale, Big Wins – Prep Chromatography Explained</h5><ul><li>We, 11.2.2026 10:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5793">Registration</a></li></ul>Learn how to scale analytical methods to preparative HPLC, optimize loading capacity, and understand the limits of preparative columns for pharmaceutical applications.<h5>3. ALS Czech Republic: PFAS in Food &amp; Food Contact Material</h5><ul><li>We, 11.2.2026 15:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5816">Registration</a></li></ul>Get a practical overview of PFAS in food and food contact materials, including EU and US regulations, key analytical challenges, and reliable PFAS testing strategies.<h5>4. 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://lcms.labrulez.com/webinar/5720">Registration</a></li></ul>Explore how fermentation-driven innovation is transforming functional food ingredients and how advanced analytics optimize flavour, functionality, and stability.<h5>5. SCIEX: Accurate Mass Fundamentals – Interpreting and Applying Your Data</h5><ul><li>We, 11.2.2026 19:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5772">Registration</a></li></ul>Session 3 focuses on interpreting and applying accurate mass data to confirm compound identity, move beyond basic quantitation, and troubleshoot results for confident reporting.<h5>6. Agilent Technologies: Process Analytical Techniques – Online HPLC for Real-Time Monitoring and Control of Bioprocesses</h5><ul><li>Th, 12.2.2026 06:30 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5834">Registration</a></li></ul>Discover how PAT HPLC enables near-real-time monitoring of critical quality attributes in bioprocessing, with a case study on charge-variant control by cation-exchange chromatography.<h5>7. Thermo Fisher Scientific: Introducing the Orbitrap Excedion Pro Hybrid MS</h5><ul><li>Th, 12.2.2026 11:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5889">Registration</a></li></ul>Discover the new Orbitrap Exploris Pro with expanded ETD/EThcD capabilities for confident biopharmaceutical characterization, including intact proteins, PTMs, ADCs, and large biomolecules.<h5>8. Waters Corporation: Planning Your NuGenesis Upgrade – Insights and Best Practices for a Smooth Transition</h5><ul><li>Th, 12.2.2026 19:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5833">Registration</a></li></ul>Learn how to plan a successful NuGenesis upgrade, transition to Windows 11, and unlock new capabilities such as dashboards for real-time operational insights.<h5>9. Thermo Fisher Scientific: Comprehensive Analytical Strategies for Peptide Therapeutics and GLP-1 Agonists with Agilent</h5><ul><li>Th, 12.2.2026 19:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5814">Registration</a></li></ul>Explore analytical workflows for peptide therapeutics, including method development, peptide mapping, GLP-1 QC, and LC-MS strategies across Agilent platforms.<h5>10. Agilent Technologies: Moving from R&amp;D and Limited QC on a UV-Vis-NIR Instrument to Large-Scale QC Using an Autosampler</h5><ul><li>Th, 12.2.2026 20:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/2104">Registration</a></li></ul>This webinar covers practical aspects of adding and using an autosampler to maximize UV-Vis-NIR QC workflows at scale.<h5>11. Agilent Technologies: LC Method Transfer – Hidden Challenges &amp; Absolute Solution</h5><ul><li>Fr, 13.2.2026 06:30 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/webinar/5787">Registration</a></li></ul>Discover why LC method transfer between legacy and modern systems is challenging, which hidden parameters affect retention and peak shape, and how to achieve robust, reliable results.

Webinars LabRulezLCMS Week 07/2026

Charge detection mass spectrometry (CDMS) allows direct mass determination of individual ions and is increasingly used to study heterogeneous biological samples. This work demonstrates the use of Orbitrap-based CDMS/Direct Mass Technology (DMT) for quantitative analysis of transthyretin (TTR) tetramer samples below 100 kDa, extending CDMS beyond its traditional qualitative role.DMT resolved wild-type and C-terminally modified TTR homotetramers, as well as hybrid tetramers, enabling kinetic analysis of subunit exchange and stability. The approach also quantified thyroxine binding to TTR variants, revealing differences in binding affinity linked to C-terminal modification. By separating overlapping m/z signals through charge measurement, CDMS enables accurate mass and abundance determination, highlighting its potential for quantitative analysis of complex protein systems.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771">Dissecting Heterogeneous Populations of Protein-Complex Samples Using Direct Mass Technology</a></h4>Robert L. Rider, Jared Hampton, Zhenyu Xi, Carter Lantz, Sangho D. Yun, Weijing Liu, Rosa Viner, Arthur Laganowsky, and David H. Russell*Anal. Chem. 2025, 97, 49, 27057–27063<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acs.analchem.5c05771">https://doi.org/10.1021/acs.analchem.5c05771</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.Transthyretin (TTR) is a homotetrameric transport protein that circulates in plasma and cerebrospinal fluid, delivering thyroxine (T4) and retinol-binding protein–vitamin A complexes. <a href="javascript:void(0);">(1)</a> The stability of the TTR tetramer is central to its physiological role because dissociation into monomers can initiate misfolding and amyloid formation, leading to systemic or hereditary transthyretin amyloidosis. <a href="javascript:void(0);">(2)</a> Subunit exchange between wild-type (WT) and variant TTR proteoforms, including disease-associated mutations such as V30M and V122I, have been implicated in amyloid progression by generating hybrid tetramers (tetramers containing WT and mutant subunits) with altered stabilities. <a href="javascript:void(0);">(3,4)</a> Ligand binding, particularly at the two thyroxine-binding sites located at the dimer–dimer interface, can kinetically stabilize the tetramer and modulate amyloidogenicity. <a href="javascript:void(0);">(5,6)</a> Accurate measurement of both subunit exchange kinetics and ligand binding stoichiometry is therefore critical for elucidating the TTR dynamics and stability.Affinity or sequence tags are widely employed in protein expression, purification, or detection. <a href="javascript:void(0);">(7,8)</a> While these tags are often assumed to be inert, their influence on protein structure and dynamics are rarely examined in detail. <a href="javascript:void(0);">(9,10)</a> Protein tags at the N- and C-terminus of TTR have been shown to have differing gas phase stabilities from those of WT-TTR. <a href="javascript:void(0);">(11)</a> The C-terminus is of particular interest because this region participates in the dimer–dimer interface that governs tetramer stability. <a href="javascript:void(0);">(11,12)</a> Characterizing how the C-terminal tag (CT) (-ASGENLFYQ) affects TTR’s solution stability and ligand binding is not only relevant for understanding TTR dynamics but also provides an example of how expression tags can alter protein dynamics. <a href="javascript:void(0);">(13)</a>Native mass spectrometry (nMS) has been invaluable for characterizing protein complexes, <a href="javascript:void(0);">(14)</a> yet conventional nMS often struggles with heterogeneous samples where overlapping charge state distributions and adduct heterogeneity limit resolution and quantitation. <a href="javascript:void(0);">(15)</a> Charge detection mass spectrometry (CDMS) addresses these limitations by independently measuring the charge and m/z of individual ions, enabling the direct determination of molecular mass and abundance. Development of CDMS has largely focused on achieving higher mass resolution <a href="javascript:void(0);">(16)</a> and extending measurements toward assemblies into the GDa range. <a href="javascript:void(0);">(17,18)</a> However, there is untapped utility for CDMS experiments other than mass and proteoform determination. Jordan et al. showed the capability to assess conformational heterogeneity of mAb aggregates using the added charge dimension that CDMS provides. <a href="javascript:void(0);">(19)</a> The current work demonstrates that CDMS can separate proteoforms with overlapping m/z values based on charge and quantify their relative abundances in complex mixtures. While nMS is already a highly quantitative technique, our results establish CDMS as an equally powerful tool for quantitative analysis in heterogeneous systems. <a href="javascript:void(0);">(20,21)</a>Here, we apply Orbitrap-based CDMS/Direct Mass Technology (DMT) using the selective temporal overview of resonant ions (STORI) approach <a href="javascript:void(0);">(22,23)</a> to quantitatively compare WT-TTR and CT-TTR, focusing on two biologically relevant properties: tetramer stability assessed via subunit exchange kinetics and ligand-binding affinity. Conventional nMS cannot fully resolve the overlapping charge states of WT- and CT-TTR or their ligand-bound states. However, DMT can resolve these species by directly measuring the mass (m/z × charge), enabling quantitation of all proteoforms. The data reveal that the CT tag alters tetramer stability and thyroxine-binding affinity, demonstrating the structural sensitivity of TTR to modifications at its C-terminus. More broadly, this work demonstrates the impact that protein tags can have on native protein interactions and highlights the broader utility of quantitative CDMS for probing heterogeneous biological samples.<h4>Experimental Section</h4><h5>Data Collection</h5>All experiments were conducted on a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/560">Thermo Scientific Q-Exactive UHMR</a> with added DMT capabilities (Bremen, Germany). Before DMT, mass spectra were collected at various resolving powers (6–200k) for each sample, with the instrument parameters reported in the Supporting Information (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acs.analchem.5c05771/suppl_file/ac5c05771_si_001.pdf">Table S1</a>). For DMT experiments, the trapping gas pressure in the HCD cell was reduced to 0.3–0.8 to attenuate the signal intensity to a single ion level, as well as decreasing the UHV pressure to assist ion retention through the entire transient of Orbitrap analysis. We observed no significant difference between mass spectra collected at various HCD cell pressures (Supporting Information, <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acs.analchem.5c05771/suppl_file/ac5c05771_si_001.pdf">Figure S1</a>). For DMT collection, automated ion control (AIC) and 100% target density were used with 200k resolving power.<h4>Results and Discussion</h4>CDMS has emerged as a powerful tool for analyzing heterogeneous biomolecular samples, enabling accurate, direct mass determination by simultaneously measuring the charge and m/z for individual ions. While CDMS has been widely applied for qualitative analyses, its potential for quantitative and less than MDa applications remains underexplored. <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig1">Figure 1</a>A shows the theoretical mass spectrum of WT-TTR (14+ to 16+) and CT-TTR (15+ to 17+) homotetramers, where the two proteoforms become increasingly resolved as the charge states increase (&lt;3900 m/z). <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig1">Figure 1</a>B zooms in on the 14+ (WT) and 15+ (CT) charge states, highlighting their strong overlap, which prevents accurate deconvolution of the proteoforms by conventional methods. <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig1">Figure 1</a>C displays theoretical distributions for 0, 1, and 2 T4 bound states of both WT- and CT-TTR tetramers, where &lt;3900 m/z has observable separation between all proteoforms. However, for the 14+ and 15+ charge states of WT- and CT-TTR, respectively, the 0 T4- and 1 T4-bound populations overlap (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig1">Figure 1</a>D). Furthermore, commonly adducted species (Na+, K+, and Zn2+) observed in experimental spectra broaden these distributions, making it increasingly difficult to distinguish and deconvolute the proteoforms (see <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acs.analchem.5c05771/suppl_file/ac5c05771_si_001.pdf">Figure S2</a>). Here, we employ Orbitrap-based CDMS/DMT to overcome this m/z overlap to resolve and quantify hybrid tetramer formation and T4 binding.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Anal_Chem_2025_97_49_27057_27063_Figure_1_A_Theoretical_mass_spectra_of_WT_TTR_and_CT_TTR_homotetramers_47232849d9.jpg" alt="Anal. Chem. 2025, 97, 49, 27057–27063: Figure 1. (A) Theoretical mass spectra of WT-TTR and CT-TTR homotetramers. (B) Zoomed-in view of the 14+ WT-TTR and 15+ CT-TTR distributions to show the large overlap of the proteoforms. (C) Theoretical mass spectra of WT-TTR and CT-TTR homotetramers with thyroxine (T4) binding. (D) Zoomed-in view of the 14+ WT-TTR and 15+ CT-TTR distributions where the 0 and 1 T4 have overlapping distributions. These theoretical distributions do not contain any commonly adducted species (Na+, K+, Zn2+), which broaden the distributions and create more overlap even for the proteoforms in the range 3300–3900 m/z (see Figure S2)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Anal_Chem_2025_97_49_27057_27063_Figure_1_A_Theoretical_mass_spectra_of_WT_TTR_and_CT_TTR_homotetramers_47232849d9.jpg 187w," sizes="100vw" width="1417" height="1182"><h5>Thyroxine Binding to TTR Homotetramers</h5>Thyroxine is the less active form of a thyroid hormone important for metabolism that binds to TTR for transport throughout plasma and cerebral spinal fluid. <a href="javascript:void(0);">(31)</a> Turnover of T4 into T3 (active) occurs after dissociation, where it can then modulate gene expression via binding to nuclear receptors. <a href="javascript:void(0);">(32)</a> The TTR tetramer gains substantial stability as it binds up to 2 T4 at the tetramer interface, decreasing tetramer dissociation and SUE. <a href="javascript:void(0);">(33)</a> This has been shown previously to decrease the amyloidogenic rate of TTR, which led to tafamidis (similar in structure to T4) to be designed and is currently the only drug that is approved for clinical treatment of TTR amyloidosis. <a href="javascript:void(0);">(34)</a> Measuring the difference in binding affinity between TTR proteoforms may provide insight into regions of TTR or TTR intermolecular/intramolecular interactions that are important for binding of small molecules such as tafamidis and T4.DMT was further applied to quantify T4 binding to WT- and CT-TTR homotetramers, highlighting the technique’s utility in probing protein–ligand interactions. <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig3">Figure 3</a>A shows a representative mass spectrum of TTR homotetramers in the presence of T4. While ligand-bound species can be observed, homotetramers cannot be confidently resolved across the entire 3000–5000 m/z range. By leveraging the charge-resolving capabilities of DMT, we achieve separation of the homotetramers (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acs.analchem.5c05771#fig3">Figure 3</a>B,C) and the 0, 1, and 2 ligand-bound states. The 2D plot clearly shows the gain in resolution achieved when charge is simultaneously measured with m/z by separating the 14+ and 15+ charge states for WT and CT, respectively, in the range 3900–4200 m/z. Additionally, using ion mobility does not provide the same kind of 2D resolution due to the similarity in arrival times for the homotetramer proteoforms, as evidenced by <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acs.analchem.5c05771/suppl_file/ac5c05771_si_001.pdf">Figures S4 and S5</a> (see the Supporting Information). These data provide evidence that when ion mobility is able to separate out species that overlap in m/z yet differ in mobility, CDMS could be an alternative or used complementarily since the species likely also differ in charge.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Anal_Chem_2025_97_49_27057_27063_Figure_3_A_Mass_spectra_of_WT_TTR_and_CT_TTR_homotetramers_with_thyroxine_binding_61b1e98a94.jpg" alt="Anal. Chem. 2025, 97, 49, 27057–27063: Figure 3. (A) Mass spectra of WT-TTR and CT-TTR homotetramers with thyroxine binding. Ligand binding can be resolved, but homotetramers cannot be confidently identified. Charge states labeled are for WT; CT is always one charge state higher at the same m/z range. (B) DMT heatmap resolving WT-TTR and CT-TTR homotetramers with the additional measurement of charge. (C) Deconvoluted mass spectrum from DMT analysis. Both homotetramers and their ligand binding are resolved, and fit for analysis is shown in red. (D) Mole fraction of each homotetramer and their thyroxine binding species. Error bars represent the standard deviation of replicates (n = 3). The significance for each ligand state is in respect to the left adjacent state. *p &lt; 0.05." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Anal_Chem_2025_97_49_27057_27063_Figure_3_A_Mass_spectra_of_WT_TTR_and_CT_TTR_homotetramers_with_thyroxine_binding_61b1e98a94.jpg 181w," sizes="100vw" width="1266" height="1094"><h4>Conclusion</h4>This work demonstrates that quantitatively, Orbitrap-based CDMS/DMT can determine differences in protein-complex stability and ligand binding. By directly comparing WT- with CT-TTR, we show that the CT tag accelerates tetramer dissociation while enhancing T4 binding affinity. These results indicate that the C-terminus, located at the dimer–dimer interface, plays a more significant role in TTR stability and ligand recognition than previously appreciated. <a href="javascript:void(0);">(12)</a> Even the addition of a short peptide sequence perturbs noncovalent interactions at the interface, likely altering solvent accessibility, and the dynamics of the thyroxine binding channel. <a href="javascript:void(0);">(37,54)</a> Such findings underscore the importance of evaluating how seemingly minor sequence modifications, such as affinity tags, can influence fundamental biophysical properties.Beyond TTR, this work positions quantitative CDMS as a broadly applicable strategy for analyzing heterogeneous protein systems, where charge domain separation overcomes the resolution limits of m/z domain measurements in traditional nMS experiments. While much of the field has emphasized extending CDMS to ultrahigh masses and maximal resolution, <a href="javascript:void(0);">(16,18)</a> our results highlight the underexplored potential of applying the method in the 1000–10,000 m/z range common to nMS experiments. This capability is directly relevant to heterogeneous membrane protein complexes, which often display broad distributions of oligomeric states, PTMs, lipid, and ligand adducts that complicate spectra. <a href="javascript:void(0);">(48,55)</a> Similarly, mAbs can oligomerize and exhibit mass heterogeneity from variable glycosylation, affecting pharmacokinetics, effector function, and stability. <a href="javascript:void(0);">(19)</a> CDMS may resolve and quantify such proteoforms in a single experiment without the need for charge reduction or chemical derivatization. <a href="javascript:void(0);">(48,56,57)</a>

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KNAUER AppliChrom® ABOA HFIP-Phil GPC Columns

AppliChrom® GPC columns for separations in HFIP with broad pore technology for GPC for analytes with challenging solution behavior

AppliChrom® GPC columns for separations in HFIP<h4>Properties:</h4><ul><li>Broad pore technology for GPC for analytes with challenging solution behavior</li><li>Separation range beween: 0.1–50 000 kDa</li><li>Range of individual porosities that can be used individually or in combination</li><li>Temperature stable between: 35–145 °C</li><li>Long column lifetime - result of the combination of optimized particle and packing technology</li><li>Low column bleed for low detector noise</li><li>Excellent reproducibility and resolution due to the advanced packing procedure</li><li>Calibration standard: PMMA or PEO &nbsp;</li><li>Recommended eluents: Hexafluoroisopropanol (HFIP), 0.1 % KTFa as modifier</li></ul><h4>Applications</h4>Crystalline highperformance polymers like:&nbsp;<ul><li>polyamides (PA), polyethylen terepthalate (PET), polybutylen terepthalate (PBT), polylactic acid (PLA), polyamid 6 (PA6), polycaprolactam, paraformaldehyde, polyoxymethylene (POM), polyacetal, several polyoxazolines</li></ul><h3>GPC &amp; SEC Columns</h3>GPC &amp; SEC systems offer solutions for various applications and laboratoriesGel permeation chromatography (GPC) and size exclusion chromatography (SEC) separate analytes by size using special columns with a porous matrix. The basic separation principle is based on the fact that smaller molecules penetrate these pores more strongly and therefore move more slowly through the matrix than larger molecules. GPC/SEC is often used as gentle and powerful purification technique or for quality control in research and development. Typical target molecules are polymers, dissolved in organic solvents for GPC, and macro biomolecules like proteins, antibodies or polysaccharides, dissolved in aqueous eluents for SEC.Separation is facilitated by selecting optimal particle and pore sizes. Therefore we offer a wide range of pore sizes (35, 100, 150, 250, 350, 500, 1000, 1500, 10E5, 10E6, 10E7 Å) and several particle sizes (5, 7, 10, 12, 20 µm) as a choice to customize for every application task.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Size_Exclusion_principle_2a432edcc1.webp" alt="KNAUER: Size Exclusion - principle" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Size_Exclusion_principle_2a432edcc1.webp 228w," sizes="100vw" width="1024" height="700"><h3>KNAUER AppliChrom® ABOA columns for aqueous SEC, organic GPC, and special applications</h3><ul><li>AppliChrom® ABOA StyDiViBe Series GPC-columns for GPC analysis of organic molecules using THF, toluene, chloroform.</li><li>AppliChrom ABOA SuperOH-P Series for aqueous GPC/SEC-analysis of mainly neutral and anionic polymers like heparins, polysaccharides, PEO, PEG,....</li><li>AppliChrom® ABOA DMSO-Phil-P Series for DMSO GPC/SEC analysis (humic substances, UF/MUF-glue, p-NIPA, many polycondensates, protein from pea or leguminosae,...)</li><li>AppliChrom® ABOA DMAc-Phil-P Series for GPC/ SEC analysis in DMAc, DMF, NMP. Good for many medium polar substances, polyoxazolines, lignin,...</li><li>AppliChrom® ABOA Cat-Phil-P Series for aqueous GPC/SEC-analysis of special aminic and polycationic polymers like p-DADMAc, PEI/ polyethylenimin, chitosan, copolymers with polyaminofunctions, but also useful for polyanions or neutral polymers like heparin or PEO/PEG, dextran or pullulan.</li><li>Seperation Ranges: 100–50 000 000 Da</li></ul><h4>You decide between classical GPC/SEC columns with conventional mixed pore technology or AppliChrom® BPT technology:</h4>Separate oligomers and polymers with the new GPC media line from AppliChrom® BPT synthesis technology for large range, high resolution separations with increased accuracy in calibration (patent pending).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Appli_Chrom_ABOA_columns_58d5d380f6.jpg" alt="KNAUER: AppliChrom® ABOA columns." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Appli_Chrom_ABOA_columns_58d5d380f6.jpg 245w," sizes="100vw" width="1379" height="718">

KNAUER Sepapure® FPLC Columns for Antibody Affinity Chromatography

 The FPLC media is functionalized either with Protein A or Protein G ligands for the binding of antibodies or antibody fragments.

FPLC media based on cross-linked agarose beads with a mean diameter of 100 µm. &nbsp;The FPLC media is functionalized either with Protein A or Protein G ligands for the binding of antibodies or antibody fragments.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Antibody_Affinity_Protein_A_and_G_08afa2179e.webp" alt="KNAUER: FPLC Column for Antibody Affinity - Protein A and G" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Antibody_Affinity_Protein_A_and_G_08afa2179e.webp 236w," sizes="100vw" width="690" height="456"><h4>Properties:</h4>Sepapure® Affinity media for antibodies or antibody fragments is designed to be used with most aqueous buffer systems. It is long lasting when correctly handled and are compatible with common CIP strategies. All Sepapure® media is stored in 20 % ethanol upon delivery. Available as prepacked 1 ml or 5 ml cartridge or as bulk material.<h4>Technical data:</h4>Agarose beads with typical loading ranges of 1 - 30 mg/l (Protein A column) or 1 - 15 mg/ml (Protein G column). The maximum operating pressure the Sepapure® columns should be used at is 3 bar, while the recommended flowrate is 1 CV/ml.<h4>Recommended application areas:</h4>Typically used in the first step („capture“) of an FPLC purification procedure.<h3>KNAUER Sepapure®&nbsp;</h3>In protein purification, a combination of different methods is needed for a successful separation. The purity of the wanted biomolecule is increased in three steps: Capture - Intermediate - PolishingIn the “capture step” the crude biomolecule is extracted from major side products. In the “intermediate step” further contaminations are removed, and the highly pure biomolecule is gained in the “polishing step”. For each step a different method and therefore different columns are used.&nbsp;FPLC Sepapure® columns are dedicated for purification of biomolecules. Sepapure® media for affinity chromatography (AC) and Ion-Exchange chromatography (IEX) is based on Agarose and depending on the specific purification mode functionalized with ligands e.g. Protein A, Ni-NTA or quaternary ammonium (Q). These FPLC media are available packed in 1 ml and 5 ml cartridges or as bulk media.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg" alt="KNAUER: FPLC Sepapure® columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg 245w," sizes="100vw" width="1372" height="562"><h5>Physical properties FPLC Sepapure® columns</h5><ul><li>Resin 100 µm Agarose particles with 4 % or 6 % crosslinking</li><li>Flowrate Recommended: 1 CV/ml</li><li>pH Stability 3 – 9 long term</li><li>Max. pressure 3 bar</li></ul>Sepapure® Desalting columns are based on Dextran with an exclusion limit of 5 kDa and available in 1 ml and 5 ml cartridges.&nbsp;<h5>Physical properties Sepapure® Desalting columns</h5><ul><li>Resin 20 – 50 µm Dextran particles</li><li>Flowrate Recommended: 1 CV/ml</li><li>Exclusion limit 5 kDa</li><li>Max. pressure 3 bar</li></ul>

KNAUER Sepapure® FPLC Columns for Tag-Affinity Chromatography

FPLC media based on cross-linked agarose beads with a mean diameter of 100 µm.  The FPLC media is functionalized with NTA ligands for His-Tag.

FPLC media based on cross-linked agarose beads with a mean diameter of 100 µm. &nbsp;The FPLC media is functionalized with NTA ligands for His-Tag.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Antibody_Affinity_Protein_A_and_G_08afa2179e.webp" alt="KNAUER: FPLC Column for Tag-Affinity Chromatography" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Antibody_Affinity_Protein_A_and_G_08afa2179e.webp 236w," sizes="100vw" width="690" height="456"><h4>Properties:</h4>Sepapure® Affinity media for recombinantly tagged proteins is designed to be used with most aqueous buffer systems. It is long lasting when correctly handled and compatible with common CIP strategies. All Sepapure® media is stored in 20 % ethanol upon delivery. Available as prepacked 1 ml or 5 ml cartridge or as bulk material.<h4>Technical data:</h4>Agarose beads with typical loading ranges of 1–40 mg/l (Ni-NTA). The maximum operating pressure the Sepapure® columns should be used at is 3 bar, while the recommended flowrate is 1 CV/ml. &nbsp;Available as prepacked 1 ml or 5 ml cartridge or as bulk material.<h4>Recommended application areas:</h4>Typically used in the first step („capture“) of an FPLC purification procedure.<h3>KNAUER Sepapure®&nbsp;</h3>In protein purification, a combination of different methods is needed for a successful separation. The purity of the wanted biomolecule is increased in three steps: Capture - Intermediate - PolishingIn the “capture step” the crude biomolecule is extracted from major side products. In the “intermediate step” further contaminations are removed, and the highly pure biomolecule is gained in the “polishing step”. For each step a different method and therefore different columns are used.&nbsp;FPLC Sepapure® columns are dedicated for purification of biomolecules. Sepapure® media for affinity chromatography (AC) and Ion-Exchange chromatography (IEX) is based on Agarose and depending on the specific purification mode functionalized with ligands e.g. Protein A, Ni-NTA or quaternary ammonium (Q). These FPLC media are available packed in 1 ml and 5 ml cartridges or as bulk media.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg" alt="KNAUER: FPLC Sepapure® columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg 245w," sizes="100vw" width="1372" height="562"><h5>Physical properties FPLC Sepapure® columns</h5><ul><li>Resin 100 µm Agarose particles with 4 % or 6 % crosslinking</li><li>Flowrate Recommended: 1 CV/ml</li><li>pH Stability 3 – 9 long term</li><li>Max. pressure 3 bar</li></ul>Sepapure® Desalting columns are based on Dextran with an exclusion limit of 5 kDa and available in 1 ml and 5 ml cartridges.&nbsp;<h5>Physical properties Sepapure® Desalting columns</h5><ul><li>Resin 20 – 50 µm Dextran particles</li><li>Flowrate Recommended: 1 CV/ml</li><li>Exclusion limit 5 kDa</li><li>Max. pressure 3 bar</li></ul>

KNAUER Sepapure® FPLC Columns for Ion-Exchange Chromatography

The FPLC media is functionalized with different linkers ranging from strong anion exchange ligands to weak cation exchange ligands. 

FPLC media based on cross-linked agarose beads with a mean diameter of 100 µm. &nbsp;The FPLC media is functionalized with different linkers ranging from strong anion exchange ligands to weak cation exchange ligands.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Ion_Exchange_Chromatography_640e6f5ba7.jpg" alt="KNAUER: Sepapure FPLC Columns for Ion Exchange Chromatography" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Ion_Exchange_Chromatography_640e6f5ba7.jpg 236w," sizes="100vw" width="1920" height="1270"><h4>Properties:</h4>Sepapure® Ion-Exchange media is designed to be used with most aqueous buffer systems. It is long lasting when correctly handled and is compatible with common CIP strategies. All Sepapure® media is stored in 20 % ethanol upon delivery. &nbsp;<h4>Technical data:</h4>The agarose beads are functionalized with a quaternary ammonium for the strong anion exchanger (Q) and with diethylaminoethyl for the weak anion exchanger (DEAE). The strong cation exchanger is functionalized with sulphopropyl (SP) and the weak cation exchanger with carboxymethyl (CM).&nbsp;The maximum operating pressure the Sepapure® columns should be used at is 3 bar, while the recommended flowrate is 1 CV/ml.&nbsp;Available as prepacked 1 ml or 5 ml cartridge or as bulk material.&nbsp;<h4>Recommended application areas:</h4>Typically used in the intermediate step of an FPLC purification procedure.<h3>KNAUER Sepapure®&nbsp;</h3>In protein purification, a combination of different methods is needed for a successful separation. The purity of the wanted biomolecule is increased in three steps: Capture - Intermediate - PolishingIn the “capture step” the crude biomolecule is extracted from major side products. In the “intermediate step” further contaminations are removed, and the highly pure biomolecule is gained in the “polishing step”. For each step a different method and therefore different columns are used.&nbsp;FPLC Sepapure® columns are dedicated for purification of biomolecules. Sepapure® media for affinity chromatography (AC) and Ion-Exchange chromatography (IEX) is based on Agarose and depending on the specific purification mode functionalized with ligands e.g. Protein A, Ni-NTA or quaternary ammonium (Q). These FPLC media are available packed in 1 ml and 5 ml cartridges or as bulk media.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg" alt="KNAUER: FPLC Sepapure® columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg 245w," sizes="100vw" width="1372" height="562"><h5>Physical properties FPLC Sepapure® columns</h5><ul><li>Resin 100 µm Agarose particles with 4 % or 6 % crosslinking</li><li>Flowrate Recommended: 1 CV/ml</li><li>pH Stability 3 – 9 long term</li><li>Max. pressure 3 bar</li></ul>Sepapure® Desalting columns are based on Dextran with an exclusion limit of 5 kDa and available in 1 ml and 5 ml cartridges.&nbsp;<h5>Physical properties Sepapure® Desalting columns</h5><ul><li>Resin 20 – 50 µm Dextran particles</li><li>Flowrate Recommended: 1 CV/ml</li><li>Exclusion limit 5 kDa</li><li>Max. pressure 3 bar</li></ul>

KNAUER Sepapure® FPLC Desalting Columns

Desalting columns based on dextran for group separations of large molecular weight biomolecules from small molecular weight compounds and salts.

FPLC media based on dextran beads with a mean diameter of 20–50 µm. Size exclusion chromatography (SEC) separates molecules on the basis of size differences. KNAUER offers desalting columns based on dextran for group separations of large molecular weight biomolecules from small molecular weight compounds and salts.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Size_Exclusion_chromatography_fb9d43e34b.jpg" alt="KNAUER: Sepapure FPLC - Desalting or Buffer Exchange" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Size_Exclusion_chromatography_fb9d43e34b.jpg 156w," sizes="100vw" width="1500" height="1500"><h4>Properties:</h4>Sepapure® Desalting media is designed to be used for removal of small molecules below the exclusion limit and for covenient rebuffering. It is long lasting when correctly handled and compatible with common CIP strategies. All Sepapure® media is stored in 20 % ethanol upon delivery. Available as prepacked 5 ml cartridge or as bulk material.&nbsp;<h4>Technical data:</h4>The Sepapure® dextran beads have an exclusion limit of 5 kDa. The maximum operating pressure of the Sepapure® columns is 3 bar, while the recommended flowrate is 1 CV/ml.<h4>Recommended application areas:</h4>Typically used in the final step of an FPLC purification procedure or inbetween steps for fast buffer exchange.<h3>KNAUER Sepapure®&nbsp;</h3>In protein purification, a combination of different methods is needed for a successful separation. The purity of the wanted biomolecule is increased in three steps: Capture - Intermediate - PolishingIn the “capture step” the crude biomolecule is extracted from major side products. In the “intermediate step” further contaminations are removed, and the highly pure biomolecule is gained in the “polishing step”. For each step a different method and therefore different columns are used.&nbsp;FPLC Sepapure® columns are dedicated for purification of biomolecules. Sepapure® media for affinity chromatography (AC) and Ion-Exchange chromatography (IEX) is based on Agarose and depending on the specific purification mode functionalized with ligands e.g. Protein A, Ni-NTA or quaternary ammonium (Q). These FPLC media are available packed in 1 ml and 5 ml cartridges or as bulk media.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg" alt="KNAUER: FPLC Sepapure® columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_FPLC_Sepapure_columns_ad980345f3.jpg 245w," sizes="100vw" width="1372" height="562"><h5>Physical properties FPLC Sepapure® columns</h5><ul><li>Resin 100 µm Agarose particles with 4 % or 6 % crosslinking</li><li>Flowrate Recommended: 1 CV/ml</li><li>pH Stability 3 – 9 long term</li><li>Max. pressure 3 bar</li></ul>Sepapure® Desalting columns are based on Dextran with an exclusion limit of 5 kDa and available in 1 ml and 5 ml cartridges.&nbsp;<h5>Physical properties Sepapure® Desalting columns</h5><ul><li>Resin 20 – 50 µm Dextran particles</li><li>Flowrate Recommended: 1 CV/ml</li><li>Exclusion limit 5 kDa</li><li>Max. pressure 3 bar</li></ul>

KNAUER Eurospher II 100 C18 Prep HPLC Columns (USP L1)

Stationary phase Eurospher II 100 C18 Prep HPLC is the most often used stationary phase in reversed phase mode

Classical Reversed Phase columns for HPLC and UHPLC (USP L1)Most often used stationary phase in reversed phase mode. Silica gel based columns with C18 modification are available with or without endcapping. Classically endcapped phases are slightly more hydrophobic and unpolar than the not endcapped phases.<h5>Properties</h5><ul><li>Separation mechanism: Hydrophobic interaction</li><li>Ultra pure, spherical high performance HPLC phase based on silica gel</li><li>Unpolar, monomeric C18 (Octadecyl) modification, endcapped, with 16 % carbon content (~ 50 % endcapping).</li></ul><h5>Key features</h5><ul><li>High-class HPLC phase perfectly suited to take on routine analyses as well as the most ambitious chromatography tasks, classical C18 phase with ca. 50 % endcapping and resulting 16 % carbon content, outstanding mechanical and chemical stability.</li></ul><h5>Recommended application areas</h5><ul><li>acidic, basic and neutral analytes in reversed phase mode, for example sulphonamides</li><li>anabolic steroids</li><li>anti-psychotics</li><li>beta blocker</li><li>sudan dyes</li><li>phenols and preservatives</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C18_non_endcapped_6e4fce9989.webp" alt="KNAUER: C18 Non-endcapped" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C18_non_endcapped_6e4fce9989.webp 245w," sizes="100vw" width="682" height="420"><blockquote>Tip: Caution! Never use classical C18 phases with 100 % aqueous mobile phase. The hydrophobic C18 chains will collapse</blockquote>Stationary phase Eurospher II 100 C18 is provided in these column types: analytical, semi-preparative and preparative.Eurospher II 100 C18 Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 20, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul>Eurospher II 100 C18 Preparative dAX Columns with dynamic axial compression are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 25, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul><h3>KNAUER Preparative HPLC Columns</h3>The right choice for all dimensions from semi-prep to batch chromatography to SMB.<ul><li>Modifications: Reversed Phase, HILIC, Normale Phase</li><li>Max. Pressure: 400–600 bar</li><li>Column Inner Diameter (ID): 16–50 mm in our shop, more on request</li><li>Column Brands: Eurospher, Eurospher II</li><li>Safe Investment: Robustness and durability based on superior technology</li><li>Application: Easy upscaling, as all materials are available from ultra high performance to preparative scale HPLC. You can also use our upscaling calculator.</li><li>Customizable: Standard flanged hardware &amp; dAX hardware with static or dynamic axial compression available</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp" alt="KNAUER: KNAUER Preparative HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp 221w," sizes="100vw" width="1024" height="724"><h5>Preparative HPLC columns can be offered with two different hardware types:</h5><ul><li>Versatile standard flanged hardware for nearly any application task in batch chromatography</li><li>dAX Hardware with static and dynamic axial compression for an extended lifetime and multi-column chromatography like SMB processes</li></ul>

KNAUER Eurospher II 100 C18A Prep HPLC Columns (USP L1)

C18A phases can be operated under 100 % aqueous conditions without destroying the stationary phase, what is not recommended for classical C18 phases

C18A columns for polar reversed phase applications with 100 % aqueous mobile phase (USP L1)C18 stationary phase for the analysis of more polar and hydrophilic compounds in reversed phase mode (USP L1). Silica gel based columns with C18 modification with hydrophilic endcapping. Because of their modification, C18A phases can be operated under 100 % aqueous conditions without destroying the stationary phase, what is not recommended for classical C18 phases caused by their hydrophobicity.<h5>Properties</h5><ul><li>Separation mechanism: Hydrophobic and polar interaction</li><li>Ultra pure, spherical high performance HPLC phase based on silica gel</li><li>Polar, monomeric C18 (Octadecyl) modification, polar endcapping, with 10 % carbon content (~ 50 % endcapping).</li></ul><h5>Key features</h5><ul><li>C18 A phase with alternative, more polar selectivity, suited for the use with pure aqueous mobile phases, 50 % endcapping and resulting 10 % carbon content, outstanding mechanical and chemical stability, suited for analytical as well as semi preparative and preparative applications</li></ul><h5>Recommended application areas</h5><ul><li>Polar endcapped C18 phase for water soluble and polar analytes, 100 % aqueous eluents for analysis of very polar compounds:<ul><li>basic pharmaceutical ingredients</li><li>water soluble vitamins</li><li>catecholamines</li><li>as well as organic acids.</li></ul></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"><blockquote>Tip: With an endcapping the influence of nonderivatized silanol groups can be minimized. The endcapping reagent is generally a smaller silane than used for derivatisation. This treatment reduces the unwanted interaction of polar or charged analytes (acids, bases ect.) because the amount of available silanol groups is reduced.</blockquote>Stationary phase Eurospher II 100 C18A is provided in these column types: analytical, semi-preparative and preparative.Eurospher II 100 C18A Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 20, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul>Eurospher II 100 C18A Preparative dAX Columns with dynamic axial compression are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 25, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul><h3>KNAUER Preparative HPLC Columns</h3>The right choice for all dimensions from semi-prep to batch chromatography to SMB.<ul><li>Modifications: Reversed Phase, HILIC, Normale Phase</li><li>Max. Pressure: 400–600 bar</li><li>Column Inner Diameter (ID): 16–50 mm in our shop, more on request</li><li>Column Brands: Eurospher, Eurospher II</li><li>Safe Investment: Robustness and durability based on superior technology</li><li>Application: Easy upscaling, as all materials are available from ultra high performance to preparative scale HPLC. You can also use our upscaling calculator.</li><li>Customizable: Standard flanged hardware &amp; dAX hardware with static or dynamic axial compression available</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp" alt="KNAUER: KNAUER Preparative HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp 221w," sizes="100vw" width="1024" height="724"><h5>Preparative HPLC columns can be offered with two different hardware types:</h5><ul><li>Versatile standard flanged hardware for nearly any application task in batch chromatography</li><li>dAX Hardware with static and dynamic axial compression for an extended lifetime and multi-column chromatography like SMB processes</li></ul>

KNAUER Eurospher II 100 C18H Prep HPLC Columns (USP L1)

C18H stationary phase with a special, high efficiency or polymeric unpolar endcapping style. Suited for the use of mobile phase in an extended pH range from typically pH 1–12. 

Hydrophobic / pH stable C18H Columns for more unpolar analytes in Reversed Phase (USP L1)C18H stationary phase with a special, high efficiency or polymeric unpolar endcapping style. Because of the high carbon content and the protection of the Silica gel these materials are also suited for the use of mobile phase in an extended pH range from typically pH 1–12.While a high endcapped C18H phase is characterized mostly by the high carbon content. A polymeric endcapped phase also provides an increased steric selectivity.<h5>Properties</h5><ul><li>Separation mechanism: Hydrophobic interaction</li><li>Ultra pure, spherical high performance HPLC phase based on silica gel</li><li>Nonpolar, monomeric C18 (Octadecyl) modification, high efficiency endcapping with 17 % carbon content (~ 99 % endcapping)</li></ul><h5>Key features</h5><ul><li>Nonpolar C18 phase with high efficiency endcapping and 17 % carbon content, resulting in higher pH stability in the range of 1–12, outstanding mechanical and chemical stability, suited for analytical as well as semi preparative and preparative applications.</li></ul><h5>Recommended application areas</h5><ul><li>Recommended alternative to Kromasil 100 C18, for acidic, basic and neutral analytes in reversed phase mode with extended pH range.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C18_H_c5531f7d87.webp" alt="KNAUER: C18H" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C18_H_c5531f7d87.webp 226w," sizes="100vw" width="687" height="475"><blockquote>Tip: All analytical KNAUER columns can be used in reversed flow direction for example for cleaning. Please refer to our Column care and use documents on the website for further information about storage conditions and cleaning procedures.</blockquote>Stationary phase Eurospher II 100 C18H is provided in these column types: analytical, semi-preparative and preparative.Eurospher II 100 C18H Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 20, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul>Eurospher II 100 C18H Preparative dAX Columns with dynamic axial compression are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 25, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul><h3>KNAUER Preparative HPLC Columns</h3>The right choice for all dimensions from semi-prep to batch chromatography to SMB.<ul><li>Modifications: Reversed Phase, HILIC, Normale Phase</li><li>Max. Pressure: 400–600 bar</li><li>Column Inner Diameter (ID): 16–50 mm in our shop, more on request</li><li>Column Brands: Eurospher, Eurospher II</li><li>Safe Investment: Robustness and durability based on superior technology</li><li>Application: Easy upscaling, as all materials are available from ultra high performance to preparative scale HPLC. You can also use our upscaling calculator.</li><li>Customizable: Standard flanged hardware &amp; dAX hardware with static or dynamic axial compression available</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp" alt="KNAUER: KNAUER Preparative HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp 221w," sizes="100vw" width="1024" height="724"><h5>Preparative HPLC columns can be offered with two different hardware types:</h5><ul><li>Versatile standard flanged hardware for nearly any application task in batch chromatography</li><li>dAX Hardware with static and dynamic axial compression for an extended lifetime and multi-column chromatography like SMB processes</li></ul>

KNAUER Eurospher II 100 C18P Prep HPLC Columns (USP L1)

KNAUER´s most unpolar C18P phase with excellent shape selectivity. It features polymeric, high efficiency endcapping of 99 % and 20 % carbon content, exceptional pH stability in the range of 1–12.

C18P columns with trifunctional modifications (USP L1): Hydrophobic and stearic interactionsKNAUER´s most unpolar C18P phase with excellent shape selectivity. It features polymeric, high efficiency endcapping of 99 % and 20 % carbon content, exceptional pH stability in the range of 1–12, and outstanding mechanical and chemical stability.<h5>Properties</h5><ul><li>Separation mechanism: Hydrophobic and stearic interaction</li><li>Ultra pure, spherical high performance HPLC phase based on silica gel</li><li>Unpolar, trifunctional C18 (Octadecyl) modification, high efficiency endcapping, with 20 % carbon content (~ 99 % endcapping)&nbsp;</li></ul><h5>Key features</h5><ul><li>KNAUER´s most unpolar C18 phase, polymeric, high efficiency endcapping of 99 % and 20 % carbon content, higher pH stability in the range of 1-12, outstanding mechanical and chemical stability, suited for analytical as well as semi preparative and preparative applications.</li></ul><h5>Recommended application areas</h5><ul><li>Alternative selectivity to standard C18; stationary phase in Eurospher II C18 family with the highest carbon load; fully endcapped; excellent shape selectivity and pH stability.</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C18_P_f093126fa9.webp" alt="KNAUER: C18P" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C18_P_f093126fa9.webp 245w," sizes="100vw" width="278" height="174"><blockquote>Tip: Not all C18 phases are comparable! When replacing an existing column, always have a close look at the characteristics like carbon load, pore size and specific surface area.</blockquote>Stationary phase Eurospher II 100 C18P is provided in these column types: analytical, semi-preparative and preparative.Eurospher II 100 C18P Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 20, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul>Eurospher II 100 C18P Preparative dAX Columns with dynamic axial compression are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 25, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul><h3>KNAUER Preparative HPLC Columns</h3>The right choice for all dimensions from semi-prep to batch chromatography to SMB.<ul><li>Modifications: Reversed Phase, HILIC, Normale Phase</li><li>Max. Pressure: 400–600 bar</li><li>Column Inner Diameter (ID): 16–50 mm in our shop, more on request</li><li>Column Brands: Eurospher, Eurospher II</li><li>Safe Investment: Robustness and durability based on superior technology</li><li>Application: Easy upscaling, as all materials are available from ultra high performance to preparative scale HPLC. You can also use our upscaling calculator.</li><li>Customizable: Standard flanged hardware &amp; dAX hardware with static or dynamic axial compression available</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp" alt="KNAUER: KNAUER Preparative HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp 221w," sizes="100vw" width="1024" height="724"><h5>Preparative HPLC columns can be offered with two different hardware types:</h5><ul><li>Versatile standard flanged hardware for nearly any application task in batch chromatography</li><li>dAX Hardware with static and dynamic axial compression for an extended lifetime and multi-column chromatography like SMB processes</li></ul>

KNAUER Eurospher II 100 C8 & C8A Prep HPLC Columns (USP L7)

C8 is a silica gel based stationary phase in reversed phase mode with alternative selectivity compared to C18 phases. 

Classical and hydrophilic/aqueous C8 columns for HPLC and UHPLC (USP L7)C8 is a silica gel based stationary phase in reversed phase mode with alternative selectivity compared to C18 phases. Compared to C18 phases, these columns show less retention due to the lower hydrophobicity.<ul><li>Ultra pure, spherical high performance HPLC phase based on silica gel</li><li>Monomeric C8 (Octyl) modification, standard endcapping, with 10 % carbon content (~ 50 % endcapping)</li></ul><h5>Properties</h5><ul><li>Separation mechanism: Hydrophobic interaction(lower compared to C18 phases)</li></ul><h5>Key features</h5><ul><li>Classical C8 phase, standard 50 % endcapping and 10 % carbon load, outstanding mechanical and chemical stability, suited for analytical as well as semi preparative and preparative applications.</li></ul><h5>Recommended application areas</h5><ul><li>Similar selectivity to C18 phase but less retention due to the lower hydrophobicity; useful for determination of:<ul><li>Water soluble vitamins</li><li>Steroids</li><li>Catecholamines</li><li>Sedatives</li></ul></li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C8_rp_non_endcapped_3f7727d3fd.webp" alt="KNAUER: C8 RP Non-endcapped" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C8_rp_non_endcapped_3f7727d3fd.webp 148w," sizes="100vw" width="304" height="321">Hydrophilic C8A phase offers an alternative, more polar selectivity. It is suited for highly polar reversed phase applications with up to 100 % aqueous mobile phases.&nbsp;<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_C8_A_e1f371165e.webp" alt="KNAUER: C8A" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_C8_A_e1f371165e.webp 198w," sizes="100vw" width="473" height="373"><blockquote>Tip: Caution! Even for short term storage all buffer solutions have to be rinsed from the column to prevent crystallization effects.</blockquote>Stationary phases Eurospher II 100 C8 and C8A are provided in these column types: analytical, semi-preparative and preparative.Eurospher II 100 C8 and C8A Preparative Standard Columns are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 20, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul>Eurospher II 100 C8 and C8A Preparative dAX Columns with dynamic axial compression are available with these parameters:<ul><li>Column length (mm): 50, 150, 250</li><li>Column ID (mm): 25, 30, 50</li><li>Particle size (µm): 5, 10, 15</li></ul><h3>KNAUER Preparative HPLC Columns</h3>The right choice for all dimensions from semi-prep to batch chromatography to SMB.<ul><li>Modifications: Reversed Phase, HILIC, Normale Phase</li><li>Max. Pressure: 400–600 bar</li><li>Column Inner Diameter (ID): 16–50 mm in our shop, more on request</li><li>Column Brands: Eurospher, Eurospher II</li><li>Safe Investment: Robustness and durability based on superior technology</li><li>Application: Easy upscaling, as all materials are available from ultra high performance to preparative scale HPLC. You can also use our upscaling calculator.</li><li>Customizable: Standard flanged hardware &amp; dAX hardware with static or dynamic axial compression available</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp" alt="KNAUER: KNAUER Preparative HPLC Columns" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Preparative_HPLC_Columns_31bc2477c3.webp 221w," sizes="100vw" width="1024" height="724"><h5>Preparative HPLC columns can be offered with two different hardware types:</h5><ul><li>Versatile standard flanged hardware for nearly any application task in batch chromatography</li><li>dAX Hardware with static and dynamic axial compression for an extended lifetime and multi-column chromatography like SMB processes</li></ul>

Products from category HPLC columns - page 20

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