▎ 摘　　要

Aim: Graphene oxide (GO) has promising applications in bioimaging, diagnostics and therapeutics. This work studied the effects of size and injection dose on the biodistribution of GO to accelerate the development of a GO-based drug. Methods: GO samples were intravenously injected into mice. The content of GO in organs/tissues at different time points was measured using an I-125-labeling technique. GO in the liver and lungs was further confirmed by both Raman spectroscopic and TEM observations. The dispersion state of GO in serum was evaluated by flow cytometry. Results: Regardless of size, GO was cleared from the blood quickly and accumulated mainly in the liver and lungs. The uptake of GO in lungs increased with increasing injection dose and size. The dispersion state (i.e., size of the GO-protein complex in blood) dominated the biodistribution. Conclusion: The size and dose of GO affected its fate in vivo. For medical applications, small-sized GO with suitable funtionalization is recommended. Original submitted 30 November 2011; Revised submitted 23 March 2012; Published online on 26 July 2012