Effect of molecular weight of chitosan on antimicrobial properties and tissue compatibility of chitosan-impregnated bacterial cellulose films

Abstract

Bacterial cellulose-chitosan (BC-C) films were developed by immersing purified BC pellicles in 1.5 ~ 2.0% (w/v) acetic acid solutions containing chitosan of varying molecular weights. Effects of different molecular weight of chitosan on physical, biological and antimicrobial properties of the composite films were investigated. The cumulative chitosan absorption capacities with Mw of 141,000, 199,000, and 263,000 were 38.43, 24.65, and 23.89 mg/cm3 of dry BC film, respectively. The cumulative release profiles of chitosan from the films strongly depended on molecular weight of chitosan and pH of solution. The order of release of chitosan from the BC-C films was dependent on molecular weight as follows: Mw 141,000 > M w 199,000 > Mw 263,000. All BC-C films showed the antimicrobial abilities against Staphylococcus aureus and Aspergillus niger but had no inhibitory effect on the growth of Escherichia coli. The BC-C films supported for adhesion, spreading and proliferation of both human skin keratinocytes and fibroblasts. The antibacterial activity against S. aureus of the BC-C with the highest Mw chitosan (263,000) was higher than those of the others. On the other hand, the BC-C films with the lowest Mw chitosan (141,000) promoted the growth of human skin cells more than those of the others. © 2014 The Korean Society for Biotechnology and Bioengineering and Springer-Verlag.