E-Liquid flavors by SBSE-TD-GC-MS

Inside the Laboratory is a joint series with LCGC International and Spectroscopy, profiling analytical scientists and their research groups at universities all over the world. This series spotlights the current chromatographic and spectroscopic research their group is conducting, and the importance of their research in analytical chemistry and specific industries.

Top-down fragmentation enables rapid characterization of phosphorylated proteins without extensive sample preparation and digestion. In this study, electron capture dissociation (ECD) was used to fragment proteoforms of the cell death-related protein, Bcl-xL. Using these methods, 85–90% sequence coverage was achieved for Bcl-xL proteoforms, allowing for effective localization of phosphorylation within minutes.

Enhanced antibody analysis using electron capture dissociation (ECD) allows for precise glycan localization in low-abundance glycopeptides. This study compares the fragmentation of trastuzumab tryptic digests using ECD and collision-induced dissociation (CID). While CID generates abundant glycan HexNAc ions at 204 m/z, ECD preserves the labile glycan group, enabling accurate site localization.

Electron capture dissociation produces distinct fragments of amino acid side chains, enabling the identification of isomeric amino acids such as leucine and isoleucine. This application note demonstrates the isomer identification workflow for peptides and intact proteins using the new Agilent ExD cell and ExDViewer software for fragment analysis.