Recent advances in functional nanostructures as cancer photothermal therapy

Abstract

Being a non-invasive and relatively safe technique, photothermal therapy has attracted a lot of interest in the cancer treatment field. Recently, nanostructure technology has entered the forefront of cancer therapy owing to its ability to absorb near-infrared radiation as well as efficient light to heat conversion. In this study, key nanostructures for cancer therapy including gold nanoparticles, magnetite iron oxide nanoparticles, organic nanomaterials, and novel two-dimensional nanoagents such as MXenes are discussed. Furthermore, we briefly discuss the characteristics of the nanostructures of these photothermal nanomaterial agents, while focusing on how nanostructures hold potential as cancer therapies. Finally, this review offers promising insight into new cancer therapy approaches, particularly in vivo and in vitro cancer treatments.

Keywords: cancer therapy; nanostructures; near-infrared; photothermal therapy; plasmonic.

Figure 1

(A) Schematic description of localized surface plasmon resonance in metal NPs. (B) Dark-field image of NPs. (C) Scattering spectrum of a single NP. Notes: Reproduced from Xie T, Jing C, Long YT. Single plasmonic nanoparticles as ultrasensi tive sensors. Analyst. 2017;142(3):409–420, http://pubs.rsc.org/en/Content/ArticleLanding/2017/AN/C6AN01852A#!divAbstract, with permission of The Royal Society of Chemistry. Abbreviations: LSPR, localized surface plasmon resonance; NP, nanoparticle.

Figure 2

Schematic illustration of light to heat conversion by plasmonic nanostructures. Notes: Step 1 is excitation of metal nanoparticles by the absorbed light photons, which results in particle oscillation and charge separation. Step 2 is conversion of the absorbed light to heat through electron–electron relaxation and electron–phonon relaxation processes, which result in the formation of hot metallic lattice. Step 3 is cooling off the metal structure through electron–phonon coupling and phonon–phonon relaxation, which cause heat dissipation. Reproduced from Webb JA, Bardhan R. Emerging advances in nanomedicine with engineered gold nanostructures. Nanoscale. 2014;6(5):2502, http://pubs.rsc.org/en/content/articlelanding/2014/nr/c3nr05112a#!divAbstract, with permission of The Royal Society of Chemistry.