An engineered, self-propelled nanozyme as reactive oxygen species scavenger

BPQDs modified Janus Pt/SiO 2 nanomotors were constructed as self-propelled nanozymes, where asymmetric distributed Pt nanoparticles were the active centres to catalytically decomposing H 2 O 2 , O 2 - and OH. The nanozymes achieved more efficient self-diffusiophoretic motion under physiological concentration of H 2 O 2 as well as enhanced ability of eliminating OH and O 2 - , which greatly enhanced the ROS scavenging efficiency. • Introducing the concept of nanomotors into the field of nanozymes. • Systematic explores of the relationship between the motion and ROS scavenging activities of the self-propelled nanozymes. • Realized efficient motion of fuel-propelled nanomotors under physiological concentration of H 2 O 2. • The antioxidant ability of BPQDs for scavenging O 2 - and OH was exploited for the first time. The development of enzyme-mimicking nanomaterials (nanozymes) with excellent reactive oxygen species (ROS)-scavenging abilities and low biotoxicity is desired for clinical translation. The use of nanomotors as nanozymes for active ROS elimination is a novel strategy that involves rapid ROS diffusion through autonomous movement. Here, we report an engineered, self-propelled nanozyme based on a Janus Pt/SiO 2 nanomotor with Pt nanoparticle active centers, which possess GPx-like, CAT-like and SOD-like enzyme activities as well as ∙ OH scavenging ability. Nanozymes modified with black phosphorous quantum dots (BPQDs) achieved efficient self-diffusiophoretic motion under physiological concentrations of H 2 O 2 , independent of a fuel source. Moreover, the OH and O 2 - removal ability of BPQDs further improved antioxidant ability of this nanozyme. We hope that such strategy involving self-propulsion will facilitate the development of nanozymes and expand biomedical applications of nanomotors.