In-capillary enzymatic digestion beyond trypsin for the sensitive targeted bottom-up analysis of protein biomarkers by capillary electrophoresis-mass spectrometry

Abstract

Targeted bottom-up proteomics is of great interest for the straightforward, accurate, and sensitive measurement of specific protein biomarkers from surrogate peptide fragments. However, this approach typically relies on off-line enzymatic digestion with trypsin, a time-consuming step that may be inadequate for covering certain sequence regions containing important post-translational modifications (PTMs).