Synthesis poly(ethylene glycol)-poly(benzenesulfonamide serinol lactide urethane) copolymer for preparation pH sensitive hydrogel

Abstract

Benzenesulfonamide-based copolymers have attracted lots of attention due to their pH-sensitive property when the pH environment changes. In addition, the pH-sensitive copolymer hydrogels have been widely applied for tissue engineering and drug carrier due to the similarity to the extracellular matrix and high biocompatibility. These hydrogels can absorb a large amount of aqueous solution; therefore, they contain a high drug dose and controlled release under stimulated conditions. This research synthesized a new benzenesulfonamide by reacting serinol and benzenesulfonyl chloride in aqueous/organic solvent. The purified benzenesulfonamide-serinol (BS) monomers were refined by dissolving and phase separating with diethyl ether and ethyl acetate solvent. And then, the BS monomer was attached with D,L-lactide to formulate the co(benzenesulfonamide serinol - lactide) (Co(BS-L)). Herein, we polymerized the poly(ethylene glycol) - poly(benzenesulfonamide serinol - lactide urethane) (PEG-PSLU) from the Co(BS-L), poly(ethylene glycol), and hexamethylene diisocyante. The proton nuclear magnetic resonance (H1NMR) spectra and Fourier transform infrared (FTIR) spectra confirmed the formation of BS monomer and Co(BS-L). The Co(BS-L) contained the sulfonamide group and ester group on its structure, which is beneficial for synthesizing a biodegradable PEG-PSLU copolymer. The H1NMR results determined the molecular structure and proved the successful formation of PEG-PSLU. This copolymer is potential for the preparation of the pH-sensitive hydrogel for a controlled drug delivery system.