Interaction of the nitrogen-containing carbon backbone polymers with essential α-amino acids

The aim of this work is to research the interactions of water-soluble nitrogen-containing copolymers with essential amino acids in aqueous media. For this, poly(N-vinylformamide-co-N-vinylimidazole) and poly(N-vinylcaprolactam-co-N-vinylimidazole) random copolymers were synthesized by free radical polymerization. The products obtained are characterized by GPC, DLS, and FTIR. The copolymers have a narrow molecular weight distribution and low dispersity. The interactions of the obtained copolymers with histidine, proline, arginine, leucine, phenylalanine, and methionine were researched by UV spectroscopy, FTIR, and TEM. It was found that conjugation of the copolymers with amino acids correlates with the copolymer composition and hydrodynamic radius R(h), and depends on the pH of the medium and amino acid structures. It is shown that chloride anion presence in the polymer-amino acid-water systems affects the mechanism of their interactions. The research shows that the synthesized copolymers can be used for the creation of effective eco-friendly amino acid extraction systems or matrices for enzyme immobilization.