High-efficiency loading of hypocrellin B on graphene oxide for photodynamic therapy

A novel hybrid of graphene oxide (GO) and hypocrellin B (HB) was prepared using a simple noncovalent method. An efficient loading of HB on GO as high as 2 mg/mg was obtained. Mechanism analysis indicated that the π–π stacking interaction is the dominant driving force in the noncovalent interaction between HB and GO. Irradiation of HB and GO hybrid (HB–GO) results in efficient generation of singlet oxygen (1O2). In vitro studies have demonstrated the active uptake of HB–GO into the cytosol of tumor cells. Significant damage to such impregnated tumor cells was observed upon irradiation.