Gold nanoprism-nanorod face off: in vitro comparison of the heating efficiency, celular internalisation and thermoablation capacity of gold nanorods and nanoprisms

Abstract

Upon excitation of their surface plasmon resonance (SPR) band, plasmonic gold nanoparticles (AuNPs) undergo efficient light-to-heat transduction. Near-Infrared (NIR) illumination of AuNPs is currently being applied to a range of biomedical applications: in photothermal therapy (PTT) optoacoustic imaging (OI) and as thermal biosensors. The SPR bands of both triangular gold nanoprisms (AuNPrs) and gold nanorods (AuNRs) can be fine-tuned in the NIR range to exhibit strong absorption in the so-called ‘biological window’, where photothermal conversion of the absorbed light energy generates an efficient and sharp local heating effect. Typically, anisotropic AuNPs exhibit an inherent limitation to their downstream application due to time-consuming syntheses and poor synthetic yields, along with unwanted by-products and the use of cytotoxic surfactants. Our group recently reported a high-yielding synthesis of biocompatible single-crystal AuNPrs whereby the LSPR band can be fine-tuned from 800-1100 nm5. Here we discuss how these particles can be used to induce apoptosis (programmed cell death) in vitro and how their heating efficiency and ability to induce cell death compares with gold nanorods (AuNRs) of the same SPR band wavelength.