Heat generation in irradiated gold nanoparticle solutions for hyperthermia applications

Abstract

Gold nanoparticles (GNP) aided hyperthermia has demonstrated promising results in the treatment of cancer. However, most existing investigations focus only on the extinction spectra of GNP solutions, few reported the actual heat generation capability of these solutions to estimate their real potential in in-situ hyperthermia treatment. In this study, the impact of GNP clustering on the optical properties and heating capability of GNP aggregates in acidic solutions have been investi-gated. It was found that localized heat generation could be significantly enhanced (to up to 60.0 ℃) when acidic solutions were illuminated by a near infrared light source at 1.7 W/cm2. In addition, infrared thermography imaging can only detect the surface temperature during thermal treatment, leaving the localized temperature distribution inside the tissues unknown. To overcome this limita-tion, in this study, the absorbed energy during NIR irradiation in GNP solutions was obtained com-putationally by coupling the P1 approximation with the DDA calculation to predict the localized temperature change in the solutions. It was demonstrated that due to the accumulation and dissi-pation of heat, some local areas showed higher temperature increase with the hot spots being con-nected and merged over time.