Characterisation of gamma irradiated chitosan/pHEMA membranes for biomedical purposes

As a polysaccharide of natural origin, chitosan has the inherent properties of being biocompatible, biodegradable, and non-toxic. These properties make chitosan an ideal candidate for based backbone in copolymeric matrices for use in biomedical applications. Poly(hydroxyethyl methacrylate) is a synthetic hydrogel which possesses a high mechanical strength. The conjunction of these two components results in a new matrix that combines the useful properties of the synthetic pHEMA and natural chitosan. In this work chitosan/pHEMA membranes were obtained and gamma-irradiated under nitrogen atmosphere. The effect of various synthesis conditions on the chemical, physical and biological properties was evaluated. The chitosan/pHEMA membranes were characterised using FTIR spectroscopy, scanning electron microscopy and thermal analysis techniques. Its hydration capacity and its antimicrobial properties were also determined. The obtained results showed that the hydration capacity decreases in the irradiated membranes. It was also found that chitosan/pHEMA membranes present good barrier properties against microbes. (c) 2005 Elsevier B.V. All rights reserved.