Cancer Photothermal Therapy with ICG-Conjugated Gold Nanoclusters

Abstract

The coming era of precision nanomedicine demands engineered nanoparticles that can be readily translated into the clinic, like that of molecular agents, without being hindered by intrinsic size heterogeneity and long-term body retention. Herein we report that conjugation of indocyanine green (ICG), an FDA-approved near-infrared (NIR) dye, onto an atomically precise glutathione-coated Au25 (GS-Au25) nanocluster led to a molecular-like photothermal nanoparticle (ICG4–GS-Au25) with significantly enhanced ICG photostability and tumor targeting. Under weak NIR light irradiation conditions, free ICG failed to suppress tumor growth but the original tumors were completely eradicated with ICG4–GS-Au25. In the meantime, “off-target” ICG4–GS-Au25 was effectively cleared out from the body like small-molecule drugs after glutathione-mediated biotransformation in the liver. These findings highlight the merits of molecular-like nanomedicines, offering a new pathway to meet FDA’s criteria for the clinical translation of nanomedicines.

Novel albumin-binding photothermal agent ICG-IBA-RGD for targeted fluorescent imaging and photothermal therapy of cancer

“…Therefore, ICG has been employed as a kind of theranostic platform in many studies. [18][19][20] However, the instability in aqueous medium and nonspecic biodistribution in vivo of ICG hamper its clinical use as photothermal agent. 21 To overcome these limitations, ICG loaded nanoparticles which can improve the stability of ICG against light and heat and enhance specic tumor targeting ability should be developed.…”

Photosensitizer-Functionalized Nanocomposites for Light-Activated Cancer Theranostics

“…Various NIR organic dyes are endowed with photodynamic properties and show promising results in PDT-based cancer treatment [21][22][23]. Compared with ultraviolet-visible (UV-Vis) dyes for imaging and PDT, the ICG derivatives show deep tissue penetration depth, useful for imaging as well as for PTT/PDT with their good photothermal conversion upon NIR light activation [24][25][26][27]. This review provides up-to-date discussion about applications of different types of UV-Vis and NIR-activated PSs in a nanocomposite form for cancer therapy.…”

Application of Gold Nanoparticle-Based Materials in Cancer Therapy and Diagnostics

“…Gold is already used as a therapeutic method in nanomedicine, with colloidal gold, covalently linked to adenovirus vectors, used to selectively target cancer and induce hyperthermia by near-infrared (NIR) laser radiation. Moreover, gold nanoparticles have several advantages that make them suitable for photothermal cancer treatments [134,135]:…”