Chitosan-Camphor Beads as a Novel Starting Biomaterial: Insights Into Methodological Approaches for Preparation.

Abstract

Biomaterials with antimicrobial and muco-adhesive properties represent an efficient system for different applications. In this paper, a new biomaterial based on chitosan-camphor beads and their crosslinked form with glutaraldehyde was optimized. Low and high molecular weight chitosan were considered. After an optimization procedure of blank beads preparation, various strategies were used to load camphor into chitosan beads where eight different beads suspensions were characterized for their size and encapsulation efficiency of camphor. Powdered camphor was added to the chitosan solution during the beads preparation or to preformed beads while it was dissolving in water or in 2% acetic acid solution. Results showed that, camphor addition to chitosan solution led to the formation of homogeneous suspensions with reproducible and higher encapsulation efficiencies of camphor compared to the other formulations, irrespective of the chitosan weight. In addition, these beads were stable for 1 month of storage at 4°C. The camphor loaded cross-linked beads with glutaraldehyde (referred to as Cam-beads-GA) were more stable than noncross-linked beads (Cam-beads), which also demonstrated satisfactory stability results. Camphor embedding in chitosan beads was proven to occur through hydrogen bonding and potentially imine bonds by FTIR analysis. The optimized formulations constitute a suitable delivery system for other bioactive agents.