Designable dual-power micromotors fabricated from a biocompatible gas-shearing strategy

Inspired by the natural microbial swimming, artificial micro-/nanomotors can imitate the functions of these characteristic natural systems. So far, significant efforts have been invested in developing functional micromotors. However, their applications are still hindered to various degrees because the using of organic solvents, photoinitiators, chemical crosslinkers, surfactants, ultraviolet irradiation, and/or cytotoxic reagents is inevitable in most fabrication processes. Herein, a simple, flexible, biocompatible, and high-throughput gas-shearing strategy is presented for fabricating designable multifaced microspheres as aqueous micromotors with autonomous movement capacities. The fabricated micromotors consist of biocompatible sodium alginate and can be propelled by magnetic guidance or biocatalyst-mediated fuel decomposition. The motion of the micromotors may be controlled by altering their structures through changing material composition, or specifically, magnetic nanoparticle and catalyst distributions within the microspheres. The microspherical micromotors are remarkably designable, thereby resulting in a series of complex motions such as pirouette motion, linear motion, tumbling motion, curvilinear motion, and circular motion. Our results confirm the potential capability of the microspherical micromotors for widespread biomedical applications.