Laser heating of metallic nanoparticles for photothermal ablation applications

Abstract

In order to search for a suitable frequency and material with higher photothermal efficacy for hyperthermia application in cancer treatment, a comparative study on laser heating of Au/Ag nanoparticles and Ag nanowires has been conducted. It is found that gold nanoparticles are more photothermal efficient in comparison with silver nanoparticles and silver nanowires at 450nm and 532 nm. Gold nanoparticles are more heated by 532 nm laser than 450 nm laser. In contrast, silver nanoparticles show slightly less temperature rise at 532 nm than 450 nm laser. For silver nanowires, no significant photothermal effect has been observed. Size-dependent effect study indicates that the absorption efficiency of single gold nanoparticles of larger diameter is higher than that of smaller diameter, in the diameter range of 0-50nm. A mathematical model for describing the heating profile in the heating sample has been built. The mathematical model can be utilized to predict the optimal treatment size of tumor.