Synthesis and characterization of hydrogel particles containing Cibacron Blue F3G-A

The analysis of low abundance and low molecular weight biomolecules is challenging due to their labile nature and the presence of high abundance, high molecular weight species such as serum albumin, which can hinder their detection. Functionalized hydrogel particles have proven to be ideally suited for this application. We here report the synthesis of hydrogel core and core–shell particles with incorporated Cibacron Blue F3G-A, and analysis of their harvesting properties. Hydrogel particle scaffolds consisting of cross-linked N-isopropylacrylamide and allylamine copolymers were synthesized via surfactant-free precipitation polymerization, with the blue dye subsequently affixed via a nucleophilic substitution reaction. The dye-functionalized core and core–shell particles were found to efficiently harvest and sequester dilute low molecular weight peptides and proteins from solution, with the core–shell particles more effectively excluding larger proteins. Moreover, proteins bound by core and core–shell particles containing blue dye were protected from tryptic degradation. These findings suggest that core and core–shell hydrogel particles containing Cibacron Blue F3G-A constitute promising new tools for peptide/protein biomarker harvesting applications.