Surface Functionalization of Green‐synthesized Reduced Graphene Oxide with PPIX Enhances Photosensitization of Cancer Cells

Abstract Photosensitizer‐functionalized reduced graphene oxide (rGO) nanoparticles are promising materials for photodynamic therapy in cancer management. In this study, rGO is synthesized by a green route employing glucose as the reducing agent and functionalized with photosensitizer, protoporphyrin IX (PPIX) in a convenient, single‐step procedure. PPIX‐functionalized rGO exhibits photodynamic effect against cancer cells (HeLa) at 0.001 mg mL −1 under visible light illumination (635 nm). A 50% elimination of HeLa cells after 5 min irradiation is observed while very low phototoxicity (80% cell viability) is noted against normal dermal fibroblast cells. A positive correlation with ROS accumulation and increased expression of caspase‐3 in PPIX‐functionalized rGO‐treated cancer cells is also established. The results evidence a simple and cost‐effective route for developing photosensitizer‐functionalized rGO for effective and selective killing of cancer cells.