Surface modification of chitosan films by grafting with aldehyde derivatives of ethylene glycol

Abstract

Chitosan, a partially deacetylated form of chitin, is a natural polymer. Structure of chitosan contains a large number of hydroxy and amino groups which can be modified by various chemical reactions. This research focused on the reactions between the amino groups of chitosan and aldehyde derivatives of monomethoxy poly(ethylene glycol) and monomethoxy triethylene glycol by reductive alkylation. The chemical modification was performed by immersing chitosan films in ethylene glycol (EG) solution. The amount of EG attached on the films were determined by IR and NMR spectroscopy. Results from contact angle measurements suggested that surface hydrophilicity of the modified films increased. Finally, these modified films were subjected to protein adsorption study in order to assess their uses in biomidical applications. It was found that the modified films somewhat affected the adsorptivity of albumin and lysozyme.