Ultrasound assisted one-step synthesis of Au@Pt dendritic nanoparticles with enhanced NIR absorption for photothermal cancer therapy

Near-infrared (NIR) light-mediated non-invasive photothermal therapy (PTT) has attracted considerable attention for cancer treatment. Strong optical absorption located in the NIR region and high performance in converting light to heat should be emphasized for the development of ideal photothermal agents. In this report, Au@Pt bimetallic nanoparticles (Au@Pt NPs) with dendritic structure were synthesized through an ultrasound assisted one-step method in aqueous solution. The absorption of Au@Pt NPs at 808 nm was obviously enhanced compared to that of Au NPs and could be easily manipulated via the amount of Pt NPs. Au@Pt NPs exhibited excellent photostability with a photothermal conversion efficiency of 44.2%, which is significantly higher than those in most reported studies. Au@Pt NPs with thiol PEG functionalization presented improved cellular killing capacity upon NIR laser irradiation. Moreover, the potential application of Au@Pt NPs was also investigated in xenograft tumor mouse model. Overall, the remarkable therapeutic characteristics of PEGylated Au@Pt NPs provide them with great potential for future cancer treatment.