Atomically Precise Au 25 (SG) 18 Nanoclusters: Rapid Single-Step Synthesis and Application in Photothermal Therapy.

Remarkable recent advances on Au25(SR)18 nanoclusters have led to significant applications in catalysis, sensing and magnetism. However, the existing synthetic routes are complicated, particularly for the water-soluble Au25(SR)18 nanoclusters. Here we report a single-step concentration and temperature controlled method for rapid synthesis of the Au25(SR)18 nanoclusters in as little as 2 h without the need for low temperature reaction or even stirring. A systematic time-based investigation was carried out to study the effects of volume, concentration and temperature on the synthesis of these nanoclusters. Further, we discovered for the first time that the Au25(SR)18 nanoclusters exhibit excellent photothermal activities in achieving 100% cell death for MDA-MB-231 breast cancer cells at a power of 10 W/cm2 using a 808 nm laser source, demonstrating applications toward photothermal therapy.