Characterization of Sugammadex-Related Isomeric Cyclodextrin Impurities Using Cyclic Ion Mobility High-Resolution Mass Spectrometry.

Cyclic ion mobility-mass spectrometry (cIM-MS) is a powerful technique for separating and identifying isomeric mixtures of compounds. When coupled with chromatography, cIM-MS creates a multidimensional separation system, with high resolving power and peak capacity. In this study, we report the cyclic ion mobility separation and high-resolution mass spectrometry identification of four regioisomers of a Sugammadex-related impurity, abbreviated as Di-OH-SGM.

Collision-Induced Dissociation of Citrullinated Peptide Anions.

Peptide identification by positive electrospray ionization (ES+) tandem mass spectrometry (MS/MS) is a well-established strategy in proteomics. Several research groups reported the usefulness of negative electrospray ionization (ES-) for gaining complementary structural information on peptides and their post-translational modifications (PTM) compared to ES+. Fragmentation of citrullinated peptides has not been previously explored in ES-.

Stepwise Collision Energy-Resolved Tandem Mass Spectrometric Experiments for the Improved Identification of Citrullinated Peptides.

The use of tandem mass spectrometry (MS/MS) is a fundamental prerequisite of reliable protein identification and quantification in mass-spectrometry-based proteomics. In bottom-up and middle-down proteomics, proteins are identified by the characteristic fragments of their constituting peptides. Post-translational modifications (PTMs) often further complicate proteome analyses.

Collision energies: Optimization strategies for bottom-up proteomics.

Mass-spectrometry coupled to liquid chromatography is an indispensable tool in the field of proteomics. In the last decades, more and more complex and diverse biochemical and biomedical questions have arisen. Problems to be solved involve protein identification, quantitative analysis, screening of low abundance modifications, handling matrix effect, and concentrations differing by orders of magnitude.

Numerical study of bulk acoustofluidic devices driven by thin-film transducers and whole-system resonance modes.

In bulk acoustofluidic devices, acoustic resonance modes for fluid and microparticle handling are traditionally excited by bulk piezoelectric (PZE) transducers. In this work, it is demonstrated by numerical simulations in three dimensions that integrated PZE thin-film transducers, constituting less than 0.1% of the bulk device, work equally well.