Functionalized graphene/C60 nanohybrid for targeting photothermally enhanced photodynamic therapy

The unique structures and properties of nanocarbons will provide fascinating applications in biomedicine. Here we report a new strategy to combine C60 with graphene for targeting phototherapy. Folic acid (FA) and polyethylene glycol (PEG) were conjugated onto graphene oxide (GO) via an imide linkage. Using nucleophilic addition, the FA–GO–PEG/C60 nanohybrid was then prepared. The versatile platform of FA–GO–PEG for C60 dramatically improved tumor targeting, which has been demonstrated by a cellular uptake assay. Owing to the doping effect and the inhibition of aggregation, the hybridization process also significantly enhanced the phototoxicity of FA–GO–PEG/C60. More importantly, the photothermal therapy (PTT) of FA–GO–PEG/C60 can cause obvious cell damage, which may further enhance the photodynamic therapy (PDT) efficacy against cancer cells. As expected, the combined PDT and PTT treatment with FA–GO–PEG/C60 showed remarkably improved and synergistic effects compared to PTT or PDT alone. This study presents the potential of nanocarbons for synergistic phototherapy of cancer.