Synthesis And Properties Of Polysaccharide-based Biodegradable Hydrogel

In this study, a novel biodegradable crosslinker based on Iaminaria(Lam) derivatives was synthesized, and polyacrylamide hydrogels were prepared using the crosslinker. The degradation behavior and drug release properties of the hydrogels were studied.In the presence of4-dimethylaminopyridine(DMAP), Lam was grafted with glycidyl methacrylate(GMA) via nucleophilic substitution which introduced acryloyl groups onto the macromolecule chains, resulting in a novel water-soluble biodegradable crosslinker Lam-GMA. The structure of Lam-GMA was characterized by1H-NMR and FTIR. The results showed that the conversion of the graftihg reaction was high, and the graft ratio could be controlled.Polyacrylamide hydrogels were formed through copolymerization of acrylamide(AM) monomers and Lam-GMA at room temperature. The results of biodegradability tests showed that the hydrogels could break down to water-soluble linear polymers under the catalysis of lipase.Characterization volume and degradation behavior of the hydrogels were studied at physiological conditions(37℃、pH=7.4). Using bovine serum albumin (BSA) as a model macromolecular drug, drug release behavior of the hydrogels was studied. Besides, the degradation kinetics of the hydrogels under different enzyme concentrations was studied. The results showed that during the degradation process, the characterization volume of the hydrogels increased firstly and then gradually decreased. As the degree of crosslinking points increased, the degradation rate of the hydrogels decreased, and thus the time required for complete degradation of the hydrogel was incremented. BSA was slowly released during the degradation process.