Bienzymatic Spiky Janus Nanomotors Powered by Histamine.

As an important inflammatory mediator, histamine can be produced by many immune cells (mast cells, neutrophils, dendritic cells, platelets, etc.) and modulates a variety of immune events. Developing enzymatic micro/nanomotors from the perspective of immunometabolism is required but still lacking. In this work, we functionalized the histamine‐metabolizing enzyme onto the Janus Au/mSiO2 nanoparticles. Powered by the tandem catalytic decomposition of histamine initiated by a surface‐modified diamine oxidase, this nanomotor system exhibits an enhanced diffusive motion with increasing histamine concentration. At a concentration of histamine (500 mM), the motor speed reaches 9.25±1.71 μm.s−1, which is 2.3 times that of Brownian motion, and the corresponding diffusion coefficient is enhanced by 137%. This novel enzymatic nanomotor system not only expands the physiologic enzyme library for biomedical micro/nanomotors but also provides new ideas for the immune therapy of diseases targeting histamine. [ABSTRACT FROM AUTHOR]