Reduced graphene oxide (rGO) hybridized hydrogel as a near-infrared (NIR)/pH dual-responsive platform for combined chemo-photothermal therapy.

For personalized cancer treatment, developing smart biomaterials with multiple biological functions is indispensable in nanomedicine fields. In this work, we developed a highly efficient near-infrared- (NIR-) and pH-responsive carboxymethyl chitosan-functionalized reduced graphene oxide/aldehyde functionalized poly (ethylene glycol) (CMC-rGO/CHO-PEG) hydrogel, which exhibits outstanding delivery performance of antitumor drug, doxorubicin hydrochloride (DOX). CMC was functionalized on the GO nanosheets via a controllable approach in order to achieve strong NIR absorption property and good distribution of rGO. The intercalation effect of CMC-rGO complex improved rGO distribution in the 3D hydrogel, contributing to the enhanced photothermal performance of CMC-rGO/CHO-PEG hydrogel. Furthermore, potential utilization of these CMC-rGO/CHO-PEG hydrogel for drug loading was studied, which provided pH-sensitive release of DOX payload. Particularly, DOX could be released in a more efficient way under acidic environment (pH = 6.5) than that under physiological environment (pH = 7.4). Therefore, this rGO hybridized PEG hydrogel holds strategic potential as a novel drug release platform for combined chem-photothermal therapy.