pH and glucose dually responsive injectable hydrogel prepared by in situ crosslinking of phenylboronic modified chitosan and oxidized dextran

Injectable hydrogels with pH and glucose triggered drug release capability were synthesized based on biocompatible phenylboronic modified chitosan and oxidized dextran through the formation of covalent imine bond and phenylboronate ester. Rheological characterization demonstrated that the gelation rate was rapid, and the moduli of the hydrogels were able to be tuned with chemical composition as well as pH and glucose concentration of the polymer solution. Anticancer drugs could be incorporated inside the hydrogel through the in situ gel forming process and undergo a controlled release by altering pH or glucose concentration. The hydrogels had good biocompatibility with viable and proliferated cells cultured in the three dimensional matrix, and the cell proliferation was suppressed when a small amount of DOX was added, which is benefit for the application of the hydrogels as smart anticancer drug delivery system. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1235–1244