Alginate–Chitosan Blend Fibers

Abstract

Combining the inherent ability of alginate to form gels and sorb moisture with the antimicrobial activity of chitosan and other unique properties of the two polymers would provide ideal materials for various medical applications. Therefore, polyion complex fibers were prepared by combining the advantages of alginate and chitosan polymers for potential use as cartilage tissue engineering scaffolds. Since the anionic nature of alginate was not conducive for the attachment of chondrocytes, it was hypothesized that adding chitosan, a cationic polysaccharide with excellent cell adhesive properties, would improve chondrocyte adhesion [04Iwa]. Sodium alginate (6 %, Mw = 600,000) was mixed with chitosan (0.035 and 0.05 % on weight of alginate) and extruded into a CaCl₂ bath to form fibers. The influence of the addition of chitosan on the tensile properties of the alginate fibers is shown in Table 29.1. Although the addition of chitosan did not change the tensile properties of the fibers, it was found that the composite fibers had enhanced cell attachment and proliferation, in vitro [04Iwa]. SEM image of chondrocytes shown in Fig. 29.1 on the alginate fibers containing 0.05 % chitosan showed the characteristic round morphology and dense collagen II fiber formation indicating good biocompatibility.