Photo-destruction of cancer cells by NIR irradiation and graphene nano-sheets

The photo-thermal therapy using nano-materials has attracted great attention as an efficient strategy for the next generation of cancer treatments. Recently, photo-thermal therapy based on nano-materials that can be activated by a skin-penetrating NIR (Near Infra Red) irradiation has been suggested as a noninvasive, harmless, and highly efficient therapeutic technique. Graphene nano-layers synthesized by a bio-compatible method, with reduced toxicity, will be a suitable candidate for the photo-thermal therapeutic agent. A significant amount of heat is generated upon excitation with near-infrared light (NIR, 700-1100nm) which is transparent to biological species including skins. In this paper, we demonstrate destruction of solid malignant cells (colon cancer cells) by the combined treatments of biocompatible graphene nano-layers and NIR irradiation. MTT methods show that more than 85% of the cells which held with autoclaved graphene solution remained alive after 24hr. In addition, NIR laser exposure with a 250 mw diode laser (780 nm) to colon cancer cells (without graphene inclusion) for 15 min kills less than 9% of colon cancer cells but exposing the NIR beam to the graphene-added cells for 25 min kills more than 66% of the cells.