Development of Amine Derivatization LC-MS/MS Technique for Non-Targeted De Novo Peptide Sequencing in Rat Plasma After Soy Protein Administration

Abstract

Purpose: This study aimed to develop a novel peptide identification method using amine derivatization techniques for de novo sequencing of peptides, addressing challenges in non-targeted peptides analysis in rat plasma after soy protein isolate (SPI) administration.Methods: Peptides were derivatized with various amine derivatization reagents including N-succinimidyl-7-methoxycoumarin-3-carboxylate (Cou) and then applied to LC-qTOF/MS for comparison.Results: Compared to other derivatization methods, Cou derivatization-aided LC-MS/MS method found that peptide bond cleavage occurred sequentially from the N-terminus of the coumarin tag. The present method achieved peptide sequencing up to 10 residues and identified a variety of oligopeptides from plasma of male SD rats after ingestion of SPI.