Hyo-Jeong Lee,1 Jakkid Sanetuntikul,2 Eun-Sook Choi,1 Bo Ram Lee,1 Jung-Hee Kim,1 Eunjoo Kim,1 Sangaraju Shanmugam2 1Nano and Bio Research Division, 2Department of Energy Systems Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea Abstract: We describe here a simple synthetic strategy for the fabrication of carbon-coated Fe3O4 (Fe3O4@C) particles using a single-component precursor, iron (III) diethylenetriaminepentaacetic acid complex. Physicochemical analyses revealed that the core of the synthesized particles consists of ferromagnetic Fe3O4 material ranging several hundred nanometers, embedded in nitrogen-doped graphitic carbon with a thickness of ~120 nm. Because of their photothermal activity (absorption of near-infrared [NIR] light), the Fe3O4@C particles have been investigated for photothermal therapeutic applications. An example of one such application would be the use of Fe3O4@C particles in human adenocarcinoma A549 cells by means of NIR-triggered cell death. In this system, the Fe3O4@C can rapidly generate heat, causing >98% cell death within 10 minutes under 808 nm NIR laser irradiation (2.3 W cm-2). These Fe3O4@C particles provided a superior photothermal therapeutic effect by intratumoral delivery and NIR irradiation of tumor xenografts. These results demonstrate that one-pot synthesis of carbon-coated magnetic particles could provide promising materials for future clinical applications and encourage further investigation of this simple method. Keywords: graphitic carbon–encapsulated magnetic nanoparticles, iron oxide, one-pot synthesis, photothermal cancer therapy