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 0.001mgmL-1 under visible light illumination (635nm). A 50% elimination of HeLa cells after 5min 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.