Synthesis and Characterization of Thermosensitive Biomaterials Based on Chitosan

Herein, we reported a novel biocompatibility and thermosensitive amphiphilic polymer based on chitosan, which was synthesized by grafting carboxyl-terminated poly (N-vinylcaprolactam) (PNVCL-COOH) onto N-phthaloylchitosan (PHCS) via a conjugation reaction between hydroxyl and carboxyl. As a biopolysaccharide extracted from crustaceans and one of the most abundant biopolymers in nature, chitosan is currently receiving a great deal of interest for medical and pharmaceutical applications due to its interesting intrinsic properties, such as no-toxic, biocompatible, biodegradable, and cost-effect. Poly(N-vinylcaprolactam) can response to the variations in temperature. It exhibits a phase separation around the lower critical solution temperature (LCST), which calls its perspectives for applications in biochemistry and medicine. In this work, the PNVCL chains were grafted onto the backbone of hydrophobic chitosan derivatives (PHCS) in order to obtain biocompatibility and thermosensitive amphiphilic polymers. FT-IR and 1H NMR techniques were utilized to confirm the molecular structure of PHCS-g-PNVCL. The LCST was analyzed by turbidity. This biocompatible polymer should be promising stimuli-responsive materials for controlled drug release.