Hyaluronic Acid Based Azo Polymer: Synthesis, Characterization, and Photo-Responsiveness

Hyaluronic acid based azo polymer (HA-Azo-COOH) is synthesized by post-azo coupling reaction. Controllable grafting percent of azobenzene pendant is achieved by adjusting the feed ratio. In selective solvents (dimethyl sulfoxide/water), uniform colloidal aggregates of the prepared polymer can be obtained by self-assembly process. The self-assembled colloids can be elongated along the polarization direction of the irradiation laser light. The relationship between the deformation of colloids and the irradiation time is explored.