Microwave Reduced Graphene Oxide as Efficient NIR Photothermal Agent

Abstract

Current study reports the enhanced cancer cells photothermal ablation efficiency of Microwave Reduced Graphene Oxide (MRGO). Reduction of chemically exfoliated graphene oxide has been carried out using a microwave (700W for 5 minutes). The produced MRGO have been characterized with TEM, SEM, XRD, FTIR, RAMAN, AFM and UV-Vis spectroscopy. MRGO nano size sheets with average lateral dimension ~200nm, exhibited higher NIR absorption efficiency, in comparison to Graphene Oxide (GO). Photothermal efficacy (at optimized NIR laser 808 nm, power of 5.0W/cm2 for 5 min) of MRGO have been tested against human alveolar epithelial carcinoma cell (A549) and human colorectal carcinoma cells (HCT116). As a result, a significant decrease in cell viability by 84% and 80% for A549 and HCT116 cell lines respectively has been estimated. No significant toxicity has been observed with MRGO (in absence of NIR treatment) at the concentrations well above the doses needed for photothermal heating against the same cancer cells. Our study introduces MRGO as a biocompatible and efficient photothermal agent.