Thermophysical and biological responses of gold nanoparticle laser heating

Abstract

A compelling vision in nanomedicine is the use of self directed nanoparticles that can accumulate in areas of disease to perform designed functions, such as molecular delivery or destruction, endosomal release of genes or siRNA, and selective cell or tumor destruction with nano to macroscale spatiotemporal control and precision. These functions are increasingly achieved by gold nanoparticles (GNPs, such as sphere, shell or rod) that can be activated with a laser "switch". A defining aspect of this "switch" is GNP absorption of laser light and the ensuing heat generation and temperature change that can be confined or propagated through multiple scales from the nanoparticle surface up through bulk biological cells and tissues. In this critical review, we discuss the fundamental mechanisms of laser GNP heat generation, the measurement and modelling of the ensuing thermal response, and a number of the evolving biological applications dependent on this new technology (181 references).

Insight into plasmonic hot-electron transfer and plasmon molecular drive: new dimensions in energy conversion and nanofabrication

“…Second, plasmonic heating or photothermal effects arising from nonradiative LSPR decay is a major pathway of energy release of absorbed light via plasmonic NPs. 3,57 As a result of heating confined to a local area, various processes can evolve. Thermophoresis or thermodiffusion is the migration of solutes and solvents from hot to cold or vice versa triggered by temperature gradients.…”

Nanoparticles Heat through Light Localization

“…This more general case has been of particular interest for applications in biomedical imaging and for unconventional therapeutics, such as photothermal ablation of tumors. (20)(21)(22)(23)(24) To numerically solve this for the case of absorberscatterers, we simulate the fate of each incident photon passing through a random ensemble of particles. (25,26) In the limit of pure absorbers or pure scatterers this approach agrees with both the Beer-Lambert law and the diffusion approximation, respectively ( Figure S1, Supporting Information).…”

Near-IR mediated intracellular uncaging of NO from cell targeted hollow gold nanoparticles

“…13 The question is: how does one trigger this NO release in a controlled fashion? Our premise is that the rapid heating of hollow gold nanoshells (HGNs) upon excitation of the surface plasmon with NIR light [18][19][20][21] will trigger thermochemical NO release from TCF absorbed on the surface (Scheme 1). Described are the preparation of such conjugates and photoexcitation studies that validate this strategy for NO uncaging.…”

“…This band has been attributed to the plasmonic transition of these metallic nanoparticles. 18,19 Formation of the conjugates between the HGNs and the cupferron derivative TCF takes advantage of the tendency of thiols to form self-assembled monolayers on gold surfaces. 23 In order to prevent nanoparticle aggregation and improve aqueous solubility, this self-assembly was carried out with an equimolar mixture of TCF and a thiolated polyethylene glycol (TPEG, 5 kDa, purchased from Nanocs).…”