Graphene and its derivatives such as
graphene oxide (GO) have been widely explored as promising
drug delivery vehicles for improved
cancer treatment. In this review, we focus on their applications in
photodynamic therapy. The large specific surface area of GO facilitates efficient loading of the
photosensitizers and
biological molecules via various surface functional groups. By incorporation of targeting
ligands or activatable agents responsive to specific
biological stimulations, smart nanovehicles are established, enabling
tumor-triggering release or
tumor-selective accumulation of
photosensitizer for effective
therapy with minimum side effects.
Graphene-based nanosystems have been shown to improve the stability, bioavailability, and photodynamic efficiency of organic
photosensitizer molecules. They have also been shown to behave as electron sinks for enhanced visible-light photodynamic activities. Owing to its intrinsic near infrared absorption properties, GO can be designed to combine both photodynamic and photothermal
hyperthermia for optimum therapeutic efficiency. Critical issues and future aspects of
photodynamic therapy research are addressed in this review.