Preparation of chitosan/pumpkin polysaccharide hydrogel for potential application in drug delivery and tissue engineering

Biological hydrogel is important in drug delivery system and tissue engineering. In this paper, we prepared a series of biological hydrogels with N,O-carboxymethyl chitosan and oxidized pumpkin polysaccharide-II (oxidized PP-II). Morphological analyses indicated that the N,O-carboxymethyl chitosan/oxidized PP-II hydrogels (CPHs) had porous interior structures. The pore diameters ranged from several tens to several hundreds of micrometers. The storage modulus (G′) of the hydrogels ranged from 11 to 77 Pa, which indicated that the hydrogels had suitable mechanical strength. In vitro release test showed that the cumulative release of bovine serum albumin decreased from 95 to 60 % along with the proportion of oxidized PP-II to N,O-carboxymethyl chitosan from 1:1 to 1:3. After CPH-2 implanted in muscle tissues of mice for 15 days, fibroblast grew well in the CPH-2 pieces without inflammatory reaction. Therefore, the CPH-2 presented good histocompatibility with the muscle tissues of mice. Taken together, the N,O-carboxymethyl chitosan/oxidized PP-II hydrogels (CPHs) might have potential applications in the drug delivery system and tissue engineering.