Control of glycopolymer nanoparticle morphology by a one-pot, double modification procedure using thiolactones

Abstract

A copolymer from N-isopropylacryl amide (NIPAAm) and N-homocysteine thiolactone acrylamide (TlaAm), prepared by RAFT polymerization, is reacted with various amines, bearing alkyl residues of increasing length (n-propylamine, n-hexylamine, and n-dodecylamine) to liberate the corresponding thiol, which is consequently reacted in situ with 2-bromoethyl-2',3',4',6'-tetra-O-acetyl-α-d-mannopyranoside. The resulting double-modified graft copolymers show characteristic self-assembly behavior due to their amphiphilic nature, affording glycopoly-mer-based nanoparticles. While the n-propylamine-derived amphiphiles mainly lead to micelles (30 nm), the n-hexylamine adducts give rise to larger vesicles (200-600 nm). Longer alkyl amines result in the formation of large compound micelles. The assembled nanoparticles are bioactive and interact effectively with Concanavalin A (ConA).

Keywords: glycopolymer; nanoparticle; self-assembly; thio-click; thiolactone.