Retention mechanism and enrichment of glycopeptides on titanium dioxide

Abstract

A uniform method for the facile and selective enrichment of glycopeptides with titanium dioxide (TiO₂) is presented. Retention mechanisms between glycopeptides and TiO₂ were explored by checking the influence of acetonitrile content, NH₃·H₂O concentration and formic acid concentration on the retention of glycopeptides. Both hydrophilic interaction and ligand-exchange retention mechanisms between glycopeptides and TiO₂ were found to be involved. Based on this, a uniform method was established for selective enrichment of glycopeptides with TiO₂. The developed method exhibited high selectivity for N-linked glycopeptides with short to long peptide sequences. This efficient and uniform method will be a valuable tool for post-translational modification in proteomics.