Multifunctional Reduced Graphene Oxide Hydrogel as Drug Carrier for Localized and Synergic Photothermal/Photodynamics/Chemo Therapy

To combine localized drug release with multimodal therapy for malignant tumor, a composite hydrogel as an integrative drug delivery system was facilely prepared. The system contains spinach extract(SE),reduced graphene oxide(r GO) and gold nanocages(Au NCs). SE conduces to the formation of hydrogel,and also serves as a green material for improving the biocompatibility of hydrogel, and a natural photosensitizer for killing tumor cells under laser radiation(660 nm). Au NCs show obvious photothermy and can enhance the generation of cytotoxic singlet oxygen(1O2). The composite hydrogel shell on tumor cells exhibits several competitive advantages including enhanced antitumor effect by retaining the high concentration of drugs around cancer cell, excellent PDT/PTT compatibility as well as high loading and controllable release of fluorouracil(5-FU) for synergetic multimodal treatment. The survival rate of He La cells incubated with 5-FU loaded hydrogel under NIR radiation for 10 min sharply decreases to 1.2%, indicating remarkably improved antitumor effects. These results demonstrate that the hydrogel is an excellent delivery carrier for localizable, NIR-responsive and combined PTT/PDT/Chemo synergetic antitumor.