Author
Latest:
Recycle Reversed-Phase Liquid Chromatography (LC) to Achieve Separations Based on One H/D Substitution on Aromatic HydrocarbonsUltrahigh efficiency separations based on the presence of one deuterium in benzene, toluene, and naphthalene were achieved by recycle chromatography using C18 silica columns. The discrimination mechanism of H/D isotopic species is discussed based on the dispersion interactions of a CH/CD group of the solute with the stationary phase as well as the mobile phase.
Latest:
Recycle Reversed-Phase Liquid Chromatography (LC) to Achieve Separations Based on One H/D Substitution on Aromatic HydrocarbonsUltrahigh efficiency separations based on the presence of one deuterium in benzene, toluene, and naphthalene were achieved by recycle chromatography using C18 silica columns. The discrimination mechanism of H/D isotopic species is discussed based on the dispersion interactions of a CH/CD group of the solute with the stationary phase as well as the mobile phase.
Latest:
The Evolution of 3D PrintingThis is the fifth in a series of articles exploring current topics in separation science that will be addressed at the HPLC 2019 conference in Milan, Italy, from 16–20 June.
Latest:
Progress in Peak ProcessingThe advantages and limitations of several recently introduced mathematical procedures for enhancing peak resolution in liquid chromatography (LC) are described. Despite advanced separation technologies and extensive knowledge in method development, peak overlap is still commonly observed. This article gives a brief overview of the advantages and limitations of recently introduced mathematical procedures for enhancing resolution.
Latest:
Optimizing MS-Compatible Mobile Phases for IEX Separation of Monoclonal AntibodiesThe impact of ionic strength, buffer capacity, and pH-response on the retention behavior and peak shape of mAb species characterization is evaluated for IEX-MS. The aim of the present study was to understand the impact of ionic strength, buffer capacity, and pH-response on the retention behavior and peak shape of mAb species.
Latest:
Combining Different Stationary-Phase Chemistries to Improve the Selectivity of Impurity Profiling MethodsSerial coupling of different column types can provide several important benefits to the chromatographer, including fine-tuning selectivity to separate complex mixtures.
Latest:
Hydrophobic Interaction Chromatography (HIC) for the Characterization of Therapeutic Monoclonal Antibodies and Related Products, Part 2: Practical ConsiderationsIn the second part of this review of the current state of HIC, some practical considerations are explained, including method development, selection of the phase system, combined salt systems, and possibilities to combine HIC with other chromatographic modes.
Latest:
Optimizing MS-Compatible Mobile Phases for IEX Separation of Monoclonal AntibodiesThe impact of ionic strength, buffer capacity, and pH-response on the retention behavior and peak shape of mAb species characterization is evaluated for IEX-MS. The aim of the present study was to understand the impact of ionic strength, buffer capacity, and pH-response on the retention behavior and peak shape of mAb species.
Latest:
Understanding How Dwell Volume Can Affect Selectivity in Reversed-Phase Gradient ChromatographyThe effect of dwell volume on chromatographic selectivity can be successfully modelled using retention prediction software. Hence, the robustness of reversed-phase LC gradient methodologies, with respect to dwell volume, can be conveniently assessed.
Latest:
Mixing and Mixers in Liquid Chromatography, Part 3: Solutions for Problems with Sample DiluentsAdding an inline mixer between the sample injector and column in a liquid chromatography (LC) system can be an effective way to resolve problems with peak shape caused by the sample diluent.
Latest:
A Standardized 2D-LC Screening Platform for Peak Purity Determination in Pharmaceutical AnalysisThis study suggests a 2D-LC screening method to evaluate peak purity and ensure specificity in pharmaceutical analysis, thereby promoting the safe production of medicines by detecting active pharmaceutical ingredients (API) and related substances.
Latest:
Leveraging the Power of a Complementary Separation Technology to Tackle Tough Challenges in Pharmaceutical AnalysisHRIM-MS has shown unique capabilities when used to analyze cyclic peptide therapeutics, and enhances the analysis of biopharmaceuticals by efficiently filtering out interfering compounds for direct analysis within a complex mixture. These findings demonstrate the technique's utility and versatility.
Latest:
A Standardized 2D-LC Screening Platform for Peak Purity Determination in Pharmaceutical AnalysisThis study suggests a 2D-LC screening method to evaluate peak purity and ensure specificity in pharmaceutical analysis, thereby promoting the safe production of medicines by detecting active pharmaceutical ingredients (API) and related substances.
Latest:
Making Nontargeted Liquid Chromatography–High-Resolution Mass Spectrometry Analysis QuantitativeAnneli Kruve previews the topic of nontargeted liquid chromatography–high-resolution Mass spectrometry for HPLC 2019.
Latest:
Perspectives in Clinical and Pharmaceutical Solid-Phase MicroextractionBarbara Bojko previews the topic of solid-phase micoextraction for clinical and pharmaceutical research.
Latest:
Using the iDQuant Standards Kit for Pesticide Analysis to Analyse Residues in Fruits and Vegetable SamplesAB Sciex Application Note
Latest:
A Fast, Robust, and Reliable Method for Sensitively Screening Drugs of Abuse in Human Urine for Forensic ToxicologyAnalyzing drugs of abuse (DoA) in human bodily fluids is crucial for clinical research and forensic toxicology. In these routine analyses, a large number of samples must be investigated, with a potentially high laboratory cost for each sample. As such, a reliable and affordable method is required for analysis. In this article, a fast, robust, and reliable method is presented for routine, high-throughput drug screening of urine samples.
Latest:
Making the Most of Size‑Exclusion Bioseparations Using Sub‑2‑µm Column TechnologySize-exclusion chromatography (SEC) is a mainstay in the biopharmaceutical industry, serving as a gold standard analytical tool for the characterization of therapeutic proteins in development and manufacturing settings. Contemporary SEC separations can be performed using columns packed with sub-2-μm particles, and these platforms offer the highest efficiencies available for the separation of monoclonal antibody monomer species from low- and high-molecular-weight product-related impurities. Compared to other chromatographic modes used to characterize proteins, SEC is unique in that analytes are not retained by the stationary phase. As a result, special care is required to achieve in practice the chromatographic efficiency that is expected in theory. In this article, we describe the fundamental aspects of achieving high performance using sub-2-μm SEC columns. In addition, we discuss trends in the biopharmaceutical industry, including challenges that can be addressed using modern size-exclusion technologies.
Latest:
Making the Most of Size‑Exclusion Bioseparations Using Sub‑2‑µm Column TechnologySize-exclusion chromatography (SEC) is a mainstay in the biopharmaceutical industry, serving as a gold standard analytical tool for the characterization of therapeutic proteins in development and manufacturing settings. Contemporary SEC separations can be performed using columns packed with sub-2-μm particles, and these platforms offer the highest efficiencies available for the separation of monoclonal antibody monomer species from low- and high-molecular-weight product-related impurities. Compared to other chromatographic modes used to characterize proteins, SEC is unique in that analytes are not retained by the stationary phase. As a result, special care is required to achieve in practice the chromatographic efficiency that is expected in theory. In this article, we describe the fundamental aspects of achieving high performance using sub-2-μm SEC columns. In addition, we discuss trends in the biopharmaceutical industry, including challenges that can be addressed using modern size-exclusion technologies.
Latest:
Troubleshooting LC Separations of Biomolecules, Part II: Passivation and Mobile-Phase AdditivesIf you are analyzing metal-sensitive biomolecules, and a bioinert instrument is unavailable, or insufficient, passivation or mobile-phase additives may help. Here’s how to use those solutions, with tips for avoiding potential pitfalls.
Latest:
Making the Most of Size‑Exclusion Bioseparations Using Sub‑2‑µm Column TechnologySize-exclusion chromatography (SEC) is a mainstay in the biopharmaceutical industry, serving as a gold standard analytical tool for the characterization of therapeutic proteins in development and manufacturing settings. Contemporary SEC separations can be performed using columns packed with sub-2-μm particles, and these platforms offer the highest efficiencies available for the separation of monoclonal antibody monomer species from low- and high-molecular-weight product-related impurities. Compared to other chromatographic modes used to characterize proteins, SEC is unique in that analytes are not retained by the stationary phase. As a result, special care is required to achieve in practice the chromatographic efficiency that is expected in theory. In this article, we describe the fundamental aspects of achieving high performance using sub-2-μm SEC columns. In addition, we discuss trends in the biopharmaceutical industry, including challenges that can be addressed using modern size-exclusion technologies.
Latest:
Sample Preparation Made EasyWhether the application is wet, dry, or cryogenic, consistent and viable representation of sample preparation leads to more accurate and repeatable results for analysis.
Latest:
Multidimensional Separation Techniques for Characterization of BiotherapeuticsMultidimensional separations, in which two or more separation methods are coupled, are a valuable analytical tool for higher peak capacity and improved selectivity for the analysis of complex samples like biotherapeutics.
Latest:
Evaluation of Achiral Stationary Phases for Gradient Screening with Supercritical Fluid ChromatographyUnlike reversed-phase liquid chromatography, SFC lacks a universal stationary phase. Thus, it is important to re-evaluate the default column screening library used with SFC. In this study, three uncommon achiral SFC columns were investigated and compared to three popular stationary phases.
Latest:
Kinase Fragments Dimerize Without Oligomerization Domains, Shown by SEC-MALSetermination of oligomeric states is an important issue in protein chemistry. For example, self-assembly via oligomerization domains is crucial for the regulation of several protein kinases. Determination of the oligomeric state of fragments of these kinases is a means of verifying the involvement of each domain in self-assembly.
Latest:
An Uncommon Fix for LC–MS Ion SuppressionMetal-free columns should be considered when troubleshooting ion suppression. Chelating compounds that can form metal salt with stainless steel column housings are examined.
Latest:
A New HILIC Column for Saccharide AnalysisDue to the highly polar nature of saccharides, the analysis of sugars is typically achieved using hydrophilic interaction chromatography (HILIC).
Latest:
SFC–GCxGC to Analyse Matrices from Petroleum and CoalSFC–GCxGC is shown to be useful in fossil fuel analysis. Practical examples for the analysis of complex matrices are described.
