A bimetallic nanocatalyst for light-free oxygen sensitization therapy

Summary Singlet oxygen ( 1 O 2 ) is extensively employed by reactive oxygen species (ROS)-based cancer therapies, such as photodynamic therapy (PDT) and chemodynamic therapy (CDT). However, the dependences of PDT on light and CDT on complex chemodynamic reactions greatly limit their 1 O 2 -generating efficiencies. Here, we exploit strain and electronic effects to fabricate a bimetallic nanocatalyst by coating a gold nanorod (AuNR) with ~2 platinum (Pt) atomic layers (AuPt 0.09 ), which efficiently generates 1 O 2 from ground-state oxygen ( 3 O 2 ) by electron-transfer-mediated spin reduction. Density functional theory reveals strain, and electronic effects promote the adsorption of 3 O 2 onto AuPt 0.09 , which dramatically enhances 1 O 2 generation and imparts AuPt 0.09 , the highest catalytic constant ever reported for 3,3′,5,5′-tetramethylbenzidine oxidation to the best of our knowledge. With a pH-dependent catalytic activity, AuPt 0.09 realizes acidity-dependent antitumor effects both in vitro and in vivo , a proof-of-concept demonstration of autocatalytic bimetallic nanocatalyst for light-free oxygen sensitization therapy, which may open a new avenue for 1 O 2 -centered therapeutics.