Systematic synthesis of a series of glycopolymers having N-acetyl-D-glucosamine moieties that can be used for evaluations of lectin—carbohydrate interactions

Abstract

Four kinds of water-soluble carbohydrate monomers having different methylene numbers of polymerizable aglycons were systematically prepared from N-acetyl-D-glucosamine (GlcNAc). Typical radical polymerization in the presence of ammonium persulfate (APS)—tetramethylethylenediamine (TEMED) in water was applied for the monomers with acryl amide as a regulator for adjusting the average distance between carbohydrate residues, a series of glycopolymers having various densities of GlcNAc residues was obtained. Regulation of the polymers showed two pivotal points: one is the effect of lengths between carbohydrate residues and the polymer backbone and the other one is the influence of average densities of carbohydrates in the glycopolymer. Carbohydrate—protein interaction by means of the glycopolymer library for wheat germ agglutinin (WGA) as a model protein was investigated and the highest Ka value was obtained when the glycopolymer having the longest methylene length and the ratio of 1:10 (sugar unit:acrylamide unit) was used as a substrate.