NIR/pH-responsive chitosan hydrogels containing Ti3C2/AuNRs with NIR-triggered photothermal effect

Remotely multi-responsive chitosan (CS) hydrogels holds great promise in the design of anticancer drug carriers. In this paper, near-infrared (NIR)-/pH-dual responsive CS/β-GP/Ti3C2@AuNRs hybrid hydrogel was prepared based on CS/β-glycerol phosphate disodium salt (β-GP) crosslinking system embedded with NIR-responsive Ti3C2@gold nanorods (AuNRs) nanosheets. Excess β-GP promoted the formation of massive electronegative cavities, which endowed hybrid hydrogels with high drug loading efficiency for electropositive DOX (around 88.5 %). The collapse of chitosan network in acidic medium gave the hybrid hydrogel with distinct pH response. In addition, the distinct temperature increase owing to the strong NIR responsiveness of Ti3C2@AuNRs nanosheets would accelerate the DOX release dramatically. Therefore, NIR-, pH- and thermal-multi-responsiveness would synergistically endow CS/β-GP/Ti3C2@AuNRs hybrid hydrogel with notable NIR-triggered photothermal effect and remotely controllable drug delivery properties.