Retention mechanism on phosphodiester stationary phases in HILIC and purely aqueous mobile phase, Part I: The problem of hold-up volume determination.

Non-destructive chromatographic methods were used to determine the hold-up volumes of four self-packed columns containing embedded phosphate groups. The stationary phases are named Diol-P-C10, Diol-P-C18, Diol-P-Benzyl and Diol-P-Chol. The hydrophobicity of organic ligands bound to the phosphate group increases in the benzyl< decyl < octadecyl View Article and Find Full Text PDF

Diatom biosilica for liquid chromatography.

This work presents, for the first time, the preparation method and subsequent use of biosilica in column liquid chromatography in reverse-phase mode. Diatom biosilica consists of the siliceous exoskeletons (frustules) of unicellular algae. Controlled cultivation of Pseudostaurosira trainorii diatoms resulted in frustules with an average diameter of approximately 4 µm, sidewall thickness of 1 µm, and a bottom thickness of 110-150 nm.

Viral sequence determines HLA-E-restricted T cell recognition of hepatitis B surface antigen.

The non-polymorphic HLA-E molecule offers opportunities for new universal immunotherapeutic approaches to chronic infectious diseases. Chronic Hepatitis B virus (HBV) infection is driven in part by T cell dysfunction due to elevated levels of the HBV envelope (Env) protein hepatitis B surface antigen (HBsAg). Here we report the characterization of three genotypic variants of an HLA-E-binding HBsAg peptide, Env identified through bioinformatic predictions and verified by biochemical and cellular assays.

To 200,000 / and Beyond: Native Electron Capture Charge Reduction Mass Spectrometry Deconvolves Heterogeneous Signals in Large Biopharmaceutical Analytes.

Great progress has been made in the detection of large biomolecular analytes by native mass spectrometry; however, characterizing highly heterogeneous samples remains challenging due to the presence of many overlapping signals from complex ion distributions. Electron-capture charge reduction (ECCR), in which a protein cation captures free electrons without apparent dissociation, can separate overlapping signals by shifting the ions to lower charge states. The concomitant shift to higher / also facilitates the exploration of instrument upper / limits if large complexes are used.

Exploring the green frontier: Subcritical water chromatography for sustainable analytical practices.

Water in the subcritical state is characterized by properties significantly different from water under standard conditions. These include low viscosity, low surface tension, and a much lower dielectric constant, increasing the solubility of nonpolar substances. For this reason, it can provide an alternative solvent and be used in chromatographic techniques-subcritical water chromatography (SBWC).