Convalent assembly oxidized dextran/chitosan multilayer and its anti-adhesive property.

Abstract

Oxidized dextran and chitosan were alternatively deposited in a layer-by-layer way onto aminolyzed glass to construct anti-adhesive multilayer assembly. A method to assemble the layers via covalent interaction in a cheap and non-toxic method was developed in this project. The contact-angle, UV-visible spectroscopy and atomic force microscopy data verified the progressive buildup of the multilayer assembly. The results of initial adhesion of fibroblast cell, Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) on the assemblies with different layer number and outermost layer were tested. It showed that for both oxidized dextran and chitosan as outermost layer, the anti-adhesive effect against fibroblast cell increased with increasing of layer number. Anti-adhesive property against E.coli depended on the outermost layer and oxidized dextran as outermost layer gave a 99% reduction of adhesive bacteria when reaching 10 bilayer. However, all types of assemblies showed no anti-adhesive effect against S.aureus regardless of layer number and outermost layer. Such an easy and shape-independent method to prepare anti-adhesive surface may have good potential for surface modification of medical devices.