Near-Infrared Organic Dye-Based Nanoagent for the Photothermal Therapy of Cancer

Given their easy structural modification and good biocompatibility advantages, near-infrared (NIR) organic dyes with a large molar extinction coefficient, while a superlow fluorescence quantum yield shows considerable potential application in photothermal therapy (PTT). Herein, a new NIR-absorbing asymmetric cyanine dye, namely, RC, is designed and synthesized via the hybrid of rhodamine and hemicyanine derivatives. RC-BSA nanoparticles (NPs) are fabricated by using the bovine serum albumin (BSA) matrix. The NPs exhibit a strong NIR absorption peak at ∼868 nm and 28.7% photothermal conversion efficiency. Based on these features, RC-BSA NPs exhibit excellent performance in ablating tumor under a 915 nm laser radiation through a PTT mechanism. These NPs show no obvious toxicity to the treated mice. Thus, RC-BSA NPs can used as a new NIR laser-triggered PTT agent in cancer treatment.