Galactose-based polymer-containing phenylboronic acid as carriers for insulin delivery.

The galactose-based polymer is a promising drug delivery material. Herein, a new galactose-based block copolymer, termed as 6-O-vinyl sebacic acid-D-galactopyranosyl ester block 3-acrylamide phenylboric acid p(OVNG-b-AAPBA) was successfully synthesized by 'block copolymer' method. The structure of p(OVNG-b-AAPBA) was proved by nuclear magnetic hydrogen spectrum (1 HNMR) and infrared (IR), the thermal stability was observed by thermogravimetric analyzer, and the molecular weights (Mw and Mn) were demonstrated by Gel permeation chromatography (GPC). The above test results suggested that the polymer of p(OVNG-b-AAPBA) was successfully synthesized, and it had optimal molecular weight and thermal stability, which could be used for investigating the drug delivery system. Then, this block copolymer was prepared to the nanoparticle (NP), these NPs had a satisfactory morphology, and their safety was verified by MTT and chronic animal toxicology test. In addition, insulin was encapsulated by the p(OVNG-b-AAPBA) NPs, the drug loading rate and encapsulation efficiency increased with that of AAPBA in the polymer. Finally, this study confirmed that these NPs can effectively maintain the blood sugar of diabetic mice at 96 h. In conclusion, the current study suggested that the insulin-loaded galactose-based polymer-block-3-acrylamide phenylboric acid NPs had slow-release/glucose-responsive drug release performance, which might play an active role in the diabetes therapy.