Bioinspired chemical motors for self-propelled microrobots

Self-propelled chemical motors provide new tools to power machines and devices at the microscale. Inspired by the locomotion of aquatic insects, a set of motors powered by Marangoni propulsive forces generated by surface tension gradients have been developed over the years. However, Marangoni motor systems present limitations in their applications due to poor performance, short lifetime, low efficiency, poor control, and the need for hazardous fuel chemicals or hazardous environments. We have developed a self-propelled micromotor system from a cephalopod-derived protein and an anesthetic metabolite capable of operating in physiological conditions. This protein motor system surpasses previous Marangoni motors due to its dynamic nanostructure, enhancing performance by consuming less fuel (energy efficiency by controlling its release) and increasing its lifetime. These motors offer great versatility as they can be coated on a wide array of substrates and materials across length scales, with opportunities as modular power sources for microrobots and small-scale devices. These bioinspired chemical motors enable the wider design of self-powered microrobots without limitations in their swimming media, with potential applications in drug delivery and environmental remediation.