Glucose-Derived Carbonaceous Nanospheres for Photoacoustic Imaging and Photothermal Therapy

Carbon nanomaterials with small size and unique optical properties have attracted intensive interest for their promising biomedical applications. In this work, glucose-derived carbonaceous nanospheres (CNSs) with high photothermal conversion efficiency up to 35.1% are explored for the first time as a novel carbon-based theranostic agent. Different from most other carbon nanomaterials, the obtained CNSs are highly biocompatible and nontoxic because of their intrinsic hydrophilic property and the use of glucose as raw materials. Under near-infrared laser irradiation (808 nm, 6 W cm(-2)) for 10 min, less than 15% of PC-3M-IE8 cells exposed to CNSs aqueous dispersions (0.16 mg/mL) remained alive. After intravenous administration of CNSs aqueous dispersions into nude mice, the photoacoustic intensity of the tumor region is about 2.5 times higher than that of preinjection. These results indicate that CNSs are suitable for simultaneous photoacoustic imaging and photothermal ablation of cancer cells and can serve as promising biocompatible carbon-based agents for further clinical trials.