Chitosan-coated gold nanorods for cancer therapy combining chemical and photothermal effects.

To develop a novel type of nanoparticle for cancer therapy, gold nanorods (GNRs) are coated with chitosan (CS) derivatives to combine chemical and photothermal effects. Thiol-modified chitosan derivatives chemically conjugated to doxorubicin (DOX) are successfully synthesized and their in vitro effect is evaluated. Functional nanocarriers (DOX-CS-GNR) with good biocompatibility and optical properties are prepared by conjugating chitosan derivatives to GNRs. Two types of structures with different molar ratios of chitosan derivatives and GNRs are successfully obtained. In in vitro studies, GNR-loaded nanoparticles show low cytotoxicity and high potential for anti-cancer effects. Under conditions of short exposure time and low light intensity, DOX-CS-GNR nanocarriers with a side-by-side structure exhibit cytoxicity against tumor cells based on a combination of chemical and photothermal therapeutic effects.