Ag/Pd bimetal nanozyme with enhanced catalytic and photothermal effects for ROS/hyperthermia/chemotherapy triple-modality antitumor therapy

Abstract

We prepared an Ag/Pd bimetallic nanozyme with the peroxidase-like activity as a nanocarrier to load doxorubicin (DOX). It combines photothermal conversion ability and catalytic production of hydroxyl radicals (HO•) to achieve enhanced antitumor effects. The temperature rise under near-infrared (NIR) laser irradiation was recorded to demonstrate the photothermal conversion ability of the Ag/Pd bimetallic nanoparticles (AgPd NPs). The peroxidase-like activity of the AgPd NPs was visually characterized by a color rendering experiment of TMB. Compared with bare Ag NPs, bimetallic AgPd NPs exhibit better photothermal conversion capability (η = 40.97%) and catalytic ability resulting from alloying with palladium. The antitumor effect was evaluated by cell experiments and tumor-bearing mice experiments, and it was confirmed that AgPd@BSA/DOX has excellent antitumor activity in vitro and in vivo. These results indicate that the AgPd@BSA/DOX can effectively catalyze hydrogen peroxide to generate hydroxyl radicals and induce hyperthermia under the irradiation of the NIR laser while releasing the chemotherapy drug DOX to achieve triple modality treatment. Intrinsic enzymatic activity and photothermal property of AgPd@BSA/DOX can be synergized for efficient antitumor treatment, which provided a novel strategy for cancer therapy.