Indocyanine green-incorporating nanoparticles for cancer theranostics

Abstract

Indocyanine green (ICG) is a near-infrared dye that has been used in the clinic for retinal angiography, and defining cardiovascular and liver function for over 50 years. Recently, there has been an increasing interest in the incorporation of ICG into nanoparticles (NPs) for cancer theranostic applications. Various types of ICG-incorporated NPs have been developed and strategically functionalised to embrace multiple imaging and therapeutic techniques for cancer diagnosis and treatment. This review systematically summaries the biodistribution of various types of ICG-incorporated NPs for the first time, and discusses the principles, opportunities, limitations, and application of ICG-incorporated NPs for cancer theranostics. We believe that ICG-incorporated NPs would be a promising multifunctional theranostic platform in oncology and facilitate significant advancements in this research-active area.

Figure 1

Schematic illustration of three types of ICG NPs.

Figure 2

In vivo NIRF imaging of FA-INPs and free ICG in nude mice bearing MCF-7 tumors after intravenous injection. (A) Time-lapse NIRF images of nude mice (the tumors are circled with a dotted line) (B) NIRF images of organs and tumors 48 h post-injection of free ICG and FA-INPs. Reproduced with permission from ref., Copyright 2017, ACS Appl Mater Inter.

Figure 3

SWNT-ICG-RGD tumor targeting in living mice by PA imaging. (A) Illustration of SWNT-ICG NPs. ICG molecules (red color) attached to the SWNT surface via noncovalent π-π stacking bonds. SWNT-ICG-RGD tumor targeting in living mice. (B) Ultrasound (grey) and photoacoustic (green) images of one vertical slice through the tumor as indicated by the dotted black line in the photograph. SWNT-ICG-RGD showed higher accumulation in the tumor compared to control SWNT-ICG-RAD. Reproduced with permission from ref. , Copyright 2017, Nano Lett.

Figure 4

(A) Schematic illustration of the synthesis of doxorubicin- and ICG- loaded PLGA-lecithin-PEG NPs. (B) Infrared thermographic maps of mice intratumorally injected with DINP, INPs, PBS, or free ICG measured at 5 min after irradiation. (C) MCF-7 tumor growth curves of different groups after dual-modality treatment. Reproduced with permission from ref. , Copyright 2017, ACS Nano.