Local field enhanced Au/CuS nanocomposites as efficient photothermal transducer agents for cancer treatment.

Photothermal therapy (PTT) for cancer treatment is the use of heat between 41 degrees C and 45 degrees C to damage cancer cells. As a new type of transducer agent for PPT of cancer, CuS nanoparticles have several advantages over gold nanostructures. The most favorable features are the low cost, simple and easy preparation, and small size for targeting. However, the CuS nanoparticle PTT efficacy needs to be improved for practical applications. In this study, the CuS nano-PTT efficiency was enhanced via the local field enhancement from Au nanoparticle surface plasmon coupling. The results show that absorbance of CuS nanoparticles in Au/CuS nanocomposites is enhanced about 2.2 times by Au nanoparticle surface plasmon coupling. Consequently, the PTT efficacy is enhanced and a power of 0.2 W/cm2 with a 980 nm laser was sufficient for Au/CuS nano-PTT activation. We have demonstrated for the first time that surface plasmon coupling can be used to enhance CuS nanoparticle PTT for cancer treatment.