Controlled pH- and glucose-responsive drug release behavior of cationic chitosan based nano-composite hydrogels by using graphene oxide as drug nanocarrier

To realize tight control of hyperglycemia for diabetic patients, cationic chitosan (HTCC) based nano-composite hydrogels were prepared by using graphene oxide (GO) as nano-carrier for the model drug (bovine serum albumin, BSA). BSA intercalated into the layers of GO and the intercalation process was mainly driven by the mutual electrostatic interaction. By introducing GO-BSA, a more compact GO-centered network structure formed for the hydrogel. Compared with HTCC/BSA, HTCC/2.0wt%GO-BSA hydrogels exhibited a more distinct pH-/glucose-sensitivity and a much lower initial burst release, which was attributed to the compact structure and strong interactions among HTCC, GO and BSA in the hydrogel system.