▎ 摘　　要

A novel approach has been developed for the preparation of strongly green-photoluminescent graphene quantum dots (GQDs-PEG) which have been surface-passivatecl by polyethylene glycol. The photoluminescence (PL) quantum yield of the GQDs-PEG with 400 nm excitation was about 18.8%, which was higher than other GQDs reported in the literature. More importantly, the surface-passivated PEG on GQDs can not only enhance PL intensity but also load drug by hydrogen bonding. Moreover, the high specific surface area of GQDs-PEG endowed them high loading capability (2.5 mg/mg) to carry drug. The results demonstrated that the GQDs-PEG were suitable for drug carrier and cell imaging. (C) 2013 Elsevier B.V. All rights reserved.