Size-dependent joule heating of gold nanoparticles using capacitively coupled radiofrequency fields

Abstract

Capacitively coupled shortwave radiofrequency fields (13.56 MHz) resistively heat low concentrations (~1 ppm) of gold nanoparticles with a thermal power dissipation of ~380 kW/g of gold. Smaller diameter gold nanoparticles (< 50 nm) heat at nearly twice the rate of larger diameter gold nanoparticles (≥ 50 nm), which is attributed to the higher resistivity of smaller gold nanostructures. A Joule heating model has been developed to explain this phenomenon and provides critical insights into the rational design and engineering of nanoscale materials for noninvasive thermal therapy of cancer.