Polymersome-forming amphiphilic glycosylated polymers: Synthesis and characterization

Abstract

Copper-catalyzed azide-alkyne cycloaddition (CuAAC) was used to prepare glycosylated polyethylene (PE)–poly(ethylene glycol) (PEG) amphiphilic block copolymers. The synthetic approach involves preparation of alkyne-terminated PE-b-PEG followed by CuAAC reaction with different azide functionalized sugars. The alkyne-terminated PE-b-PEG was prepared by etherification reaction between hydroxyl-terminated PE-b-PEG (Mn ∼ 875 g mol−1) and propargyl bromide and azidoethyl glycosides were prepared by glycosylation of 2-azidoethanol. Atmospheric pressure solids analysis probe-mass spectrometry was used as a novel solid state characterization tool to determine the outcome of the CuAAC click reaction and end-capping of PE-b-PEG by the azidoethyl glycoside group. The aqueous solution self-assembly behavior of these amphiphilic glycosylated polymers was explored by TEM and dye solubilization studies. Carbohydrate-bearing spherical aggregates with the ability to solubilize a hydrophobic dye were observed. The potential of these amphiphilic glycosylated polymers to self-assemble via electro-formation into giant carbohydrate-bearing polymersomes was also investigated using confocal fluorescence microscopy. An initial bioactivity study of the carbohydrate-bearing aggregates is furthermore presented. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 5184–5193