Preparation of novel anisotropic gold nanoplatform as NIR absorbing agents for photothermal therapy of liver cancer and enhanced ultrasound contrast imaging

Abstract

Nanoparticles (NPs) with different shape, size, architecture and composition were studied for their application as photo-thermal agents in the area of cancer nanomedicine. Out of them, gold nanoparticles (Au NPs) depending on their in vivo biocompatibility provide a simple thermal ablation platform. However, fabrication of these Au NPs showing appropriate properties for photo-thermal function requires complex routes utilizing hazardous chemicals as capping agents which may cause in vivo concerns. In this study, the fabricated Au NPs utilizing biosynthetic approach having near-infrared (NIR) absorbance assisting photo-thermal treatment could be a possible alternative. Herein, anisotropic Au NPs were fabricated utilizing an aqueous extract of Ceratonia siliqua (carob) which acts as both stabilizing and reducing agent. The biosynthesized Au NPs were exposed to density-gradient centrifugation for the optimization of NIR absorption in 800 to 1000 nm wavelength range. Colloidal Au NPs showed outstanding contrast enrichment for ultrasound imaging, and also Au nanoplates were obtained by density gradient centrifugation can function as a NIR absorbing agent for efficient photothermal killing of Hep-G2 liver tumor cells in vitro with negligible cytotoxicity to active cells. Furthermore, the present approach recommends an innovative way for treating theranostic cancer.