Indocyanine Green‐Glycogen Conjugates for Near‐Infrared‐Triggered Photothermal Cancer Therapy

Abstract

Photothermal reagents sensitive to near‐infrared (NIR) light are promising imaging agents and therapeutics for anticancer applications because of the deep tissue penetration of NIR light, allowing for spatiotemporal control over the therapeutic activity, with minimal damage to normal tissues. Herein, a new class of NIR‐sensitive biopolymer‐based nanoparticles is presented by covalently conjugating indocyanine green (ICG) onto the surface of naturally occurring glycogen nanoparticles. The resulting ICG‐glycogen conjugates exhibit a markedly enhanced aqueous stability in comparison to free ICG molecules. Furthermore, an efficient light‐to‐heat conversion is enabled by ICG‐glycogen conjugates, as evidenced by the elevated temperatures of their aqueous solutions upon exposure to NIR light. Critically, ICG‐glycogen conjugates are capable of cell internalization, and under NIR irradiation the effective eradication of breast cancer cells, demonstrating their potential in photothermal therapy for cancer.

The sweetest polymer nanoparticles: opportunities ahead for glycogen in nanomedicine

“…These concepts can also be leveraged for external control over termination of cancer cells via , as example, photodynamic therapy. Shirinichi, et al , 28 have reported on indocyanine green (ICG) coupled bovine liver glycogen nanoparticles for treatment of breast cancer cells. The hybrid nanoparticles dramatically increased the half-life of ICG from less than 4 h, to more than 100 h, and became highly cytotoxic only after administering near-infrared (NIR) light on MDA-MB-231 human breast cancer cells.…”