Hydrophilic graphene oxide/bismuth selenide nanocomposites for CT imaging, photoacoustic imaging, and photothermal therapy.

A nanotheranostic agent has been fabricated by direct deposition of Bi ₂ Se ₃ nanoparticles on graphene oxide (GO) in the presence of polyvinylpyrrolidone (PVP) using a one-pot solvothermal method. The resulting GO/Bi ₂ Se ₃ /PVP nanocomposites show low in vitro cytotoxicity, negligible hemolytic activity and little in vivo toxicity. GO/Bi ₂ Se ₃ /PVP nanocomposites could serve as an efficient bimodal contrast agent to simultaneously enhance X-ray computed tomography imaging and photoacoustic imaging in vivo. In addition, the nanocomposites exhibit significant photothermal cytotoxicity to cancer cells under 808 nm laser irradiation. After intratumoral or intravenous injection of the nanocomposites, irreversible photothermal ablation of tumors in the mouse model is successfully achieved by using 808 nm laser irradiation. All of the positive results highlight that the GO/Bi ₂ Se ₃ /PVP nanocomposites can be developed as a promising nanoplatform for efficient tumor theranostic applications.