Fluorescent graphene quantum dots (GQDs) have attracted increasing interest
in cancer bioimaging due to their stable photoluminescence (PL), high stability, low cytotoxicity,
and good biocompatibility. In this review, we present the synthesis and chemical
modification of GQDs firstly, and then introduce their unique physical, chemical, and
biological properties like the absorption, PL, and cytotoxicity of GQDs. Finally and most
importantly, the recent applications of GQDs in cancer bioimaging are demonstrated in
detail, in which we focus on the biofunctionalization of GQDs for specific cancer cell imaging
and real-time molecular imaging in live cells. We expect this work would provide
valuable guides on the synthesis and modification of GQDs with adjustable properties for
various biomedical applications in the future.