▎ 摘　　要

A simple and green approach for the synthesis of polyphenol-functionalized reduced graphene oxide nanosheets is demonstrated, using leaf extract of Citrullus colocynthis as a deoxygenating agent. The C. colocynthis polyphenols also play a significant role as a stabilizing agent, preventing agglomeration of reduced graphene oxide nanosheets. Cytotoxicity tests showed that the both graphene oxide and Citrullus colocynthis polyphenol-stabilized reduced graphene oxide were toxic to DU145 cells; the cytotoxicity was dose dependent. Hence, C. colocynthis-mediated reduced graphene oxide may be an ideal anticancer material for biological study applications.