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Inspired by the tactic organisms in Nature that can self-direct their movement following environmental stimulus gradient, we proposed a DNase functionalized Janus nanoparticle (JNP) nanomotor system for the first time, which can be powered by ultralow nM to μM levels of DNA. The system exhibited interesting chemotactic behavior toward a DNA richer area, which is physiologically related with many diseases including tumors. In the presence of the subtle DNA gradient generated by apoptotic tumor cells, the cargo loaded nanomotors were able to sense the DNA signal released by the cells and demonstrate directional motion toward tumor cells. For our system, the subtle DNA gradient by a small amount (10 μL) of tumor cells is sufficient to induce the chemotaxis behavior of self-navigating and self-targeting ability of our nanomotor system, which promises to shed new light for tumor diagnosis and therapy.

Chemodynamic therapy (CDT) is an emerging strategy for cancer treatment based on Fenton chemistry, which can convert endogenous H 2 O 2 into toxic ·OH. However, the limited endocytosis of passive CDT nanoagents with low penetrating capability resulted in unsatisfactory anticancer efficacy. Herein, we propose the successful fabrication of a self-propelled biodegradable nanomotor system based on hollow MnO 2 nanoparticles with catalytic activity for active Fenton-like Mn 2+ delivery and enhanced CDT. Compared with the passive counterparts, the significantly improved penetration of nanomotors with enhanced diffusion is demonstrated in both the 2D cell culture system and 3D tumor multicellular spheroids. After the intracellular uptake of nanomotors, toxic Fenton-like Mn 2+ is massively produced by consuming overexpressed intracellular glutathione (GSH), which has a strong scavenging effect on ·OH, thereby leading to enhanced cancer CDT. The as-developed MnO 2 -based nanomotor system with enhanced penetration and endogenous GSH scavenging capability shows much promise as a potential platform for cancer treatment in the near future.

Inducing neural stem cells to differentiate and replace degenerated functional neurons represents the most promising approach for neural degenerative diseases including Parkinson's disease, Alzheimer's disease, etc. While diverse strategies have been proposed in recent years, most of these are hindered due to uncontrollable cell fate and device invasiveness. Here, we report a minimally invasive micromotor platform with biodegradable helical Spirulina plantensis ( S. platensis ) as the framework and superparamagnetic Fe 3 O 4 nanoparticles/piezoelectric BaTiO 3 nanoparticles as the built-in function units. With a low-strength rotational magnetic field, this integrated micromotor system can perform precise navigation in biofluid and achieve single-neural stem cell targeting. Remarkably, by tuning ultrasound intensity, thus the local electrical output by the motor, directed differentiation of the neural stem cell into astrocytes, functional neurons (dopamine neurons, cholinergic neurons), and oligodendrocytes, can be achieved. This micromotor platform can serve as a highly controllable wireless tool for bioelectronics and neuronal regenerative therapy.