Preparation and characterization of hydroxypropyl chitosan modified with collagen peptide.

Collagen peptide (COP) had been grafted to hydroxypropyl chitosan (HPCS) by using microbial transglutaminase (MTGase) as biocatalyst. HPCS was synthesized from chitosan and propylene oxide under alkali condition. The chemical structures of derivative were characterized by FT-IR and 1H NMR spectroscopy. The process conditions were optimized from the aspects of the reaction time, the reaction temperature, the molar ratio of COP and the mass ratio of MTGase to HPCS. In this study, HPCS-COP could serve not only to reduce the loss of moisture but also to absorb the moisture, and the moisture absorption and moisture retention abilities were closely related to the degree of substitution (DS) values. In addition, with the DS and concentration increase of HPCS-COP, the radical scavenging activity increased in vitro antioxidant activity. Furthermore, the methyl thiazolyl tetrazolium assay (MTT) was applied to evaluate the biocompatibility of HPCS-COP, and the result indicated that HPCS-COP with the DS of 0.34 displayed pronounced cell viability at 50ppm. Therefore, the results suggest that HPCS-COP could be potential wound dressings for clinical applications.