Chitosan-based injectable in situ forming hydrogels containing dopamine-reduced graphene oxide and resveratrol for breast cancer chemo-photothermal therapy

Strategies combining nanomaterials’ chemotherapy and photothermal therapy hold an enormous potential for improving cancer treatment. Still, the translation of this modality has been hindered by the immunogenicity triggered by some of the polymers used for coating nanomaterials as well as by the nanostructures’ poor tumor uptake after systemic administration. To address this bottleneck, the formulation of injectable polymeric matrices capable of delivering/confining chemotherapeutics and nanomaterials into the tumor site has been gathering a great interest. In this work, ionotropically crosslinked chitosan-based injectable in situ forming hydrogels co-incorporating Dopamine-reduced graphene oxide (DOPA-rGO; photothermal nano-agent) and Resveratrol (RES; chemotherapeutic drug), were prepared for the first time, to be applied in cancer chemo-photothermal therapy. The formulated hydrogels displayed injectability and in situ gelation as well as suitable physicochemical properties and good cytocompatibility. In vitro, the hydrogels’ photothermal therapy ([email protected] +NIR light) only diminished the breast cancer cells’ viability to 72%. Moreover, cancer cells exposed to the hydrogels’ chemotherapy ([email protected]) still displayed a viability of 75%. In stark contrast, the hydrogels’ chemo-photothermal therapy ([email protected] +NIR light) was capable of decreasing cancer cells’ viability to just 31%. Overall, [email protected] presents an enormous potential for the chemo-photothermal therapy of breast cancer cells.