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>

Dissecting Heterogeneous Populations of Protein-Complex Samples Using Direct Mass Technology

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Thermo Scientific Syncronis PREP HILIC HPLC Columns

Maintain consistent, predictable separations for your scale up purification needs with Thermo Scientific™ Syncronis™ HILIC preparative HPLC columns for polar and hydrophilic analytes.

Maintain consistent, predictable separations for your scale up purification needs with Thermo Scientific™ Syncronis™ HILIC preparative HPLC columns for polar and hydrophilic analytes. Highly pure, high surface area silica and dense stationary phase coverage minimize secondary interactions and deliver reproducible high-resolution separations.&nbsp;The zwitterionic stationary phase results in a neutral, highly polar surface and provides optional selectivity to C18 columns without ion-pairing or derivatization. Our columns come in a wide range of dimensions and an option for XtendedLife hardware which improves column lifetime by maintaining a uniform packed bed.<h5>Alternative Selectivity</h5><ul><li>Zwitterionic bonded phase enhances retention of polar and hydrophilic analytes.</li><li>No need for ion-pair or derivatization.</li><li>Enhanced sensitivity with MS detection.</li><li>Highly organic mobile phase facilitates desolvation in ESI-MS</li></ul>Preparative HPLC Column Hardware Options - based on column inner diameter (i.d.) and column performance needs.<h5>Standard Threaded and Standard Flange Hardware</h5><ul><li>Designed for standard applications, expertly packed and robustly designed to provide versatile products for routine use.</li><li>Standard threaded hardware for column i.d. &lt; 40mm.</li><li>Standard flange hardware for column i.d. ≥ 40mm.</li><li>Standard hardware can be modified on request to be compatible with SFC.</li></ul><h5>XtendedLife Hardware</h5><ul><li>Improves column lifetime by incorporating an internal Dynamic Axial Compression (DAC) system, ensuring the media bed is continuously packed tightly.</li><li>Compatible with SFC and is available in dimensions up to 50mm i.d.</li></ul>Preparative Guards are a proven and cost effective way to extend the lifetime of your prep column. Our preparative guard columns require the use of a preparative guard holder.<h4>Specifications</h4><ul><li>Column type: HILIC</li><li>Endcapped: No</li><li>Max. Pressure: 2000 psi (140 bar)</li><li>Packing Material: Spherical, Fully Porous, Ultrapure Silica</li><li>Stationary phase: Zwitterionic</li><li>Surface Area: 320 m2/g</li><li>Temperature: 60°C</li><li>Carbon load: 5%</li><li>Phase: HILIC</li><li>Pore Size: 100 Å</li><li>pH: 2 to 8</li></ul><h4>Syncronis HPLC and UHPLC Columns</h4><h5>Enter a new world of chromatography</h5>When developing a new method, one of the most important goals for the chromatographer is to achieve a consistent, reproducible separation. This makes selecting an HPLC column that offers highly-reproducible results essential to attaining this goal.<h5>Features of Syncronis columns</h5>Thermo Scientific Syncronis LC columns achieve high levels of consistency and reproducibility through:<ul><li>Highly-pure, high-surface-area silica</li><li>Dense bonding and double endcapping</li><li>Stringent manufacturing and testing protocols</li></ul>

Thermo Scientific Dionex IonPac AS10 IC Columns

Analyze trace-levels of inorganic anions and organic acids using isocratic or gradient methods with the Thermo Scientific™ Dionex™ IonPac™ AS10 IC Column.

Analyze trace-levels of inorganic anions and organic acids using isocratic or gradient methods with the Thermo Scientific™ Dionex™ IonPac™ AS10 IC Column. Its high capacity permits the analysis of trace-level analytes in high-ionic-strength matrices. Use the Dionex IonPac AS10 column for the analysis of inorganic anions in high nitrate samples.<h5>Superior Chromatographic Performance in High Nitrate Samples</h5><ul><li>Excellent resolution of weakly retained low-molecular-weight aliphatic acids</li><li>Selectivity and high capacity for analysis of trace-level analytes in high-ionic-strength matrices</li><li>Strongly retains nitrate for high-resolution analysis of trace anions in nitric acid and nitrate salts</li></ul><h5>For Best Results</h5><ul><li>Use a Dionex eluent generator for simplified eluent preparation for applications using less than 100mN hydroxide</li><li>Use the Thermo Scientific™ Dionex™ Anion Self-Regenerating Suppressor (ASRS™ 300) with the Dionex IonPac AS10 column for continuous suppression of traditional eluents and more concentrated eluents up to 200mM NaOH</li></ul><h4>Specifications</h4><ul><li>Crosslinking: 55% DVB</li><li>Column Capacity: 170 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Separation of Inorganic Anions and Organic Acids</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS10</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li><li>pH: 0 to 14</li></ul>

Thermo Scientific Dionex IonPac AS11 IC Columns

Resolve a large number of inorganic anions and organic acids in approximately 15 minutes with the Thermo Scientific Dionex IonPac AS11 Analytical & Guard Column. 

Resolve a large number of inorganic anions and organic acids in approximately 15 minutes with the Thermo Scientific™ Dionex™ IonPac™ AS11 Analytical &amp; Guard Column. The Dionex IonPac AS11 is a relatively low-capacity column designed for fast gradient screening of inorganic anions and organic acid anions in simple sample matrices such as from foods, beverages, chemical process solutions, wastewaters, brines, and power plant waters.<h5>Superior Chromatographic Performance:</h5><ul><li>Facilitates rapid analysis of organic acids and inorganic anions in well-characterized samples</li><li>Ideal for highly charged anions, including polyphosphates and polycarboxylates</li><li>Resolves organic acids and inorganic anions in complex sample matrices</li><li>Shortens analysis time and speeds throughput</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 45 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 45 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Analysis of Inorganic and Organic Acid Anions</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS11</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li><li>pH: 0 to 14</li></ul>

Thermo Scientific Dionex IonPac AS12A IC Columns

Thermo Scientific Dionex IonPac AS12A Analytical and Guard Columns resolve trace chloride and sulfate in high-carbonate samples

Separate inorganic anions and oxyhalides, such as chlorite and bromate, in environmental samples. The Thermo Scientific™ Dionex™ IonPac™ AS12A Analytical and Guard Columns resolve trace chloride and sulfate in high-carbonate samples and meet or exceed the requirements of U.S EPA Methods 300.0 (A) and (B). However, the advanced, high-capacity IonPac AS23 Carbonate Eluent Anion-Exchange column is recommended for determination of oxyhalides and inorganic anions, such as trace bromate, in ozonated drinking water.<h5>Fast Isocratic Separation of Inorganic Anions and Oxyhalides in Diverse Matrices</h5><ul><li>Compliance monitoring of common anions in drinking water as specified in U.S. EPA Method 300.0 (A) and (B)</li><li>Separation of common inorganic anions and oxyhalides including chlorite, bromate and chlorate in less than 12 minutes</li><li>Superior retention and quantification of fluoride</li><li>Trace analysis of chloride and sulfate in high-carbonate samples</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4x200mm, 2x200mm analytical columns</li><li>4x50mm, 2x50mm guard columns</li><li>Longer 200mm columns facilitate higher resolution separations of more complex sample matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 52 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 52 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Separation of Inorganic Anions</li><li>Ion Exchange Group: Alkyl Quaternary Ammonium</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS12A</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS11-HC IC Columns

Resolve a large number of inorganic anions and organic acid anions in complex matrices with the Thermo Scientific Dionex IonPac AS11-HC Capillary, Analytical & Guard Column.

Resolve a large number of inorganic anions and organic acid anions in complex matrices with the Thermo Scientific™ Dionex™ IonPac™ AS11-HC Capillary, Analytical &amp; Guard Column. Complex sample matrices such as chemical wastewater effluents and fermentation broth solutions contain a variety of inorganic anions and organic acids. With the high-capacity Dionex IonPac AS11-HC column, you can inject higher concentration samples without column overloading or peak broadening.The Dionex IonPac AS11-HC column was specifically designed to resolve analytes in a single run using a hydroxide gradient. The high-capacity column delivers improved separation for monovalent carboxylic acids including: quinate, lactate, acetate, propionate, formate, and butyrate.<h5>High Capacity for Higher Resolution</h5><ul><li>Requires longer retention times, but with higher resolution</li><li>Facilitates rapid analysis of organic acids and anions in well-characterized samples</li><li>Ideal for organic acids and anions in complex sample matrices or uncharacterized samples</li><li>Recommended for monovalent and divalent organic acids</li></ul><h5>Reduce Operating Costs With Lower Eluent Requirements</h5>The new Dionex IonPac AS11-HC Capillary column is packed with the same material as the equivalent standard bore and microbore versions (providing the same performance as a 4mm and 2mm column) using only 1% of the eluent flow rate, which helps reduce operating costs.Use the Thermo Scientific™ Dionex™ IonPac™ ICE-AS1 or ICE-AS6 columns for organic acids in high-ionic-strength samples.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 290 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 290 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS11-HC</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS14 IC Columns

Deliver excellent results for fast isocratic separations of inorganic anions in diverse matrices with the Thermo Scientific Dionex IonPac AS14 Carbon Eluent Anion-Exchange Column.

Deliver excellent results for fast isocratic separations of inorganic anions in diverse matrices with the Thermo Scientific™ Dionex™ IonPac™ AS14 Carbon Eluent Anion-Exchange Column. This universal column for the separation of inorganic anions delivers improved peak resolution and retention of fluoride in applications performed previously with the Dionex IonPac AS4A, AS4A-SC and AS12A columns, however, the Dionex IonPac AS22 Carbonate Eluent Anion-Exchange column, an advanced carbonate eluent column, is recommended for fast analysis of inorganic anions.<h5>Fast Separation of Inorganic Anions in Diverse Matrices</h5><ul><li>Compliance monitoring of common anions in drinking water as specified in U.S. EPA Method 300.0 (A)</li><li>Separation of common inorganic anions in 13 min in drinking water, wastewater, food &amp; beverages, scrubber solutions, and other diverse sample matrices</li><li>Superior retention and quantification of fluoride, glycolate, acetate, and formate</li><li>Compatible with a sodium tetraborate gradient to optimize difficult separations</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4x250mm, 2x250mm analytical columns</li><li>4x50mm, 2x50mm guard columns</li><li>Longer 25mm columns facilitate higher resolution separations of more complex sample matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul>Note: Use with the Dionex IonPac AS14 Eluent Concentrate for simple, accurate eluent preparation.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 65 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 65 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Analysis of Fluorides and Other Inorganic Anions</li><li>Ion Exchange Group: Alkyl Quaternary Ammonium</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 2 to 12, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS14</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li><li>pH: 2 to 12</li></ul>

Thermo Scientific Dionex IonPac AS14A IC Columns

Thermo Scientific Dionex IonPac AS14A IC Column is high capacity anion-exchange column for fast isocratic separation of inorganic anions in environmental matrices

Deliver fast isocratic separation of inorganic anions from diverse and complex matrices such as drinking water, wastewater, foods and beverages, and scrubber solutions with the Thermo Scientific™ Dionex™ IonPac™ AS14A Carbon Eluent Anion-Exchange Column. The Dionex IonPac AS14A column meets or exceeds the requirements of U.S EPA Method 300.0 (A). However, the Dionex IonPac AS22 Carbonate Eluent Anion-Exchange column, an advanced carbonate eluent column, is recommended for fast analysis of inorganic anions. For the fastest separation of inorganic anions using a carbonate/bicarbonate eluent, the Dionex IonPac AS22-Fast column is recommended.<h5>Fast Separation of Inorganic Anions in Diverse Matrices</h5><ul><li>Compliance monitoring of common anions in drinking water as specified in U.S. EPA Method 300.0 (A)</li><li>Separation of common inorganic anions in 8 min (3 x 150mm format) or 13 min (4 x 250mm format) in diverse sample matrices</li><li>Superior retention and quantification of fluoride</li><li>Compatible with sodium or potassium hydroxide gradient to optimize difficult separations</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4x250mm, 3x150mm analytical columns</li><li>4x50mm, 3x30mm guard columns</li><li>Longer 250mm columns facilitate higher resolution separations of more complex sample matrices</li><li>Shorter 150mm columns produce faster runs of relatively clean matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul>Note: Use with the Dionex IonPac AS14 Eluent Concentrate and the Combined Seven Anion Standard for simple, accurate eluent preparation.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 65 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 120 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkyl Quaternary Ammonium</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 2 to 11, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS14A</li><li>Format: Standard Bore</li><li>pH: 2 to 11</li></ul>

Thermo Scientific Dionex IonPac AS15 IC Columns

Determine trace-level concentrations of inorganic anions and low-molecular-weight organic acids in high-purity water matrices with the Thermo Scientific Dionex IonPac AS15 Capillary, Analytical & Guard Columns.

Determine trace-level concentrations of inorganic anions and low-molecular-weight organic acids in high-purity water matrices with the Thermo Scientific™ Dionex™ IonPac™ AS15 Capillary, Analytical &amp; Guard Columns. Specifically designed for analysis of trace anions in high-purity water matrices used by the semiconductor and power generation industries, the column delivers high sensitivity and superior resolution of early-eluting anions (e.g., fluoride, glycolate, acetate, and formate). The column is optimized for selective at an operating temperature of 30°C, and it is ideal for use with large-loop injections.<h5>Available in Multiple Formats</h5><ul><li>Dionex IonPac AS15-5μm (3x150mm) column for high efficiency, fast analysis (15 min)</li><li>Dionex IonPac AS15-9μm (2x250mm, 4x250mm, and 0.4x250mm) columns for higher-capacity applications</li><li>Dionex IonPac AS15 capillary column (0.4x250mm) delivers the performance of the standard bore version but requires only 1% of the eluent flow rate, which helps reduce operating costs</li></ul><h5>For Best Performance</h5><ul><li>Use the Thermo Scientific™ Dionex™ IonPac™ AC15 Concentrator column for ultratrace (part per trillion) analyses</li><li>Use a Dionex eluent generator for simplified eluent preparation</li><li>Use the Thermo Scientific™ Dionex™ Anion Self-Regenerating Suppressor (ASRS™ 300) or the Thermo Scientific™ Dionex™ Anion Capillary Electrolytic Suppressor (ACES™ 300) with the Dionex IonPac AS15 column for eluent suppression</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 225 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 225 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS15</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS16 IC Columns

Measure trace perchlorate and other highly polarizable anions quickly and accurately in a variety of water matrices with the Thermo Scientific Dionex IonPac AS16 IC Columns.

Measure trace perchlorate and other highly polarizable anions quickly and accurately in a variety of water matrices with the Thermo Scientific™ Dionex™ IonPac™ AS16 IC Columns . This column simplifies the determination of polarizable anions, including thiosulfate, iodide, thiocyanate, and perchlorate using an isocratic hydroxide eluent. It is ideally suited for determination of trace perchlorate in drinking water in accordance with U.S. EPA Methods 314.0 and 314.1 (Primary Method).<h5>Designed for Simple, Sensitive Analysis</h5><ul><li>Easily measure trace concentrations of perchlorate in drinking water, surface water, and ground water matrices using a large-loop injection</li><li>Separate hydrophobic anions (iodide, thiocyanate, and thiosulfate) in less than 20 min</li><li>Ideal for polyvalent anions, including polyphosphates and polycarboxylates</li><li>Ultralow hydrophobicity allows fast analysis of polarizable anions</li><li>Can be used in the second dimension of the 2D-IC method for the analysis of trace perchlorate (sub ppb) in drinking water</li></ul><h5>Available in Multiple Formats</h5><ul><li>Standard bore (4x250mm) and microbore (2x250mm) formats</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 170 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 170 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS16</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS17-C IC Columns

Quickly determine common inorganic anions in high-purity water matrices with the Thermo Scientific Dionex IonPac AS17-C column. 

Quickly determine common inorganic anions in high-purity water matrices with the Thermo Scientific™ Dionex IonPac AS17-C column. This low-capacity column is optimized for fast gradient separation of inorganic anions in simple sample matrices. It is also ideal for fast gradient separation of sulfur species, including sulfite, sulfate, and thiosulfate. The Dionex IonPac AS17C column is the recommended replacement for all Dionex IonPac AS17 column anion applications.<h5>Make Gradient Separations as Easy as Isocratic Runs</h5>The Dionex IonPac AS17-C column is designed to be used in conjunction with the Dionex Eluent Generator. The Dionex Eluent Generator automatically produces potassium hydroxide eluents from water, making gradient separations as easy as isocratic runs. Using the Dionex Eluent Generator under gradient conditions, common inorganic anions can easily be separated in a variety of sample matrices including high purity water, drinking water, wastewater, process streams, and scrubber solutions.<h5>Achieve Superior Chromatographic Performance</h5><ul><li>Fast gradient separation of inorganic anions in high purity water matrices</li><li>Easy suppression of hydroxide eluent to a very low background with the Thermo Scientific™ Dionex™ Anion Self-Regenerating Suppressor (ASRS™ 300) for trace level determinations (including fluoride) even with a large loop injection</li><li>Superior retention and quantification of fluoride, acetate, propionate, and formate</li><li>Meets performance requirements specified in U.S. EPA Method 300.0 (A)</li><li>Operates at ambient or elevated temperatures</li><li>Column selectivity is optimized for operating temperature of 30°C to ensure reproducible results</li><li>Compatible with Reagent-Free™ Ion Chromatography (RFIC™) systems</li><li>Compatible with organic solvents to enhance analyte solubility, modify column selectivity, or for effective column clean-up</li></ul>Note: The Thermo Scientific™ Dionex™ IonPac™ AS18 column is the recommended hydroxide-selective column for determination of common anions in diverse sample matrices.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 30 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 30 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS17-C</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

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