Absolute quantitative analysis of intact and oxidized amino acids by LC-MS without prior derivatization.

ABSTRACT: The precise characterization and quantification of oxidative protein damage is a significant challenge due to the low abundance, large variety, and heterogeneity of modifications. Mass spectrometry (MS)-based techniques at the peptide level (proteomics) provide a detailed but limited picture due to incomplete sequence coverage and imperfect enzymatic digestion. This is particularly problematic with oxidatively modified and cross-linked/aggregated proteins. There is a pressing need for methods that can quantify large numbers of modified amino acids, which are often present in low abundance compared to the high background of non-damaged amino acids, in a rapid and reliable fashion. We have developed a protocol using zwitterionic ion-exchange chromatography coupled with LC-MS to simultaneousl

SUBMITTER: Gamon LF 

PROVIDER: S-EPMC7276450 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature