Synthesis and characterization of gold nanorods and their application for photothermal cell damage

BACKGROUND: Gold nanorods show a surface plasmon resonance (SPR) band at the near infra-red (NIR) region which enables them to produce heat on irradiation with a NIR laser. As a result of this, gold nanorods have the potential to be used as thermal therapeutic agents for selective damage to cancer cells, bacterial cells, viruses, and DNA. METHODS: Gold nanorods with an aspect ratio of approximately 5 were prepared by exploiting the normal micellar route of a water/dioctyl sulfosuccinate (Aerosol-T)/hexane system. The shape and size of the gold nanorods were characterized by surface plasmon bands at 520 nm and 980 nm, and by atomic force microscopy and transmission electron microscopy. RESULTS: The length of the gold nanorods was 100 nm and their diameter was 20 nm. X-ray diffraction analysis demonstrated that the gold nanorods formed were metallic in nature. The gold nanorods showed good photothermolysis activity. CONCLUSION: Gold nanorods injected subcutaneously and irradiated with 980 nm laser caused injury to rat tissue, demonstrating that gold nanorods may be used to kill cancerous cells in tumor tissue.