SCbots: Stomatocyte-like colloidosomes as versatile microrobots fabricated by one-step self-assembly

Abstract

Building microrobots with asymmetric shapes is crucial to generate net driving forces, whereas often suffer from complex fabrication processes and limited availability of materials. Additionally, integrating diverse components into a single microscopic device for multifunctional microrobots is more challenging; however, if achieved, it offers promise for advanced microrobots with significantly expanded capabilities. Our group pioneered the fabrication of stomatocyte-like colloidosomes (SCs) as motherships, on which different functional components could be conveniently loaded to construct versatile microrobots (SCbots) via one-step self-assembly. It is the first time for self-assembly of enzyme powered microrobots via colloidosomes, the mechanism governing the formation of the target SCbots possessing asymmetrical narrow-opening stomatocyte shape is demonstrated. An additional benefit of SCbots is that their speed can be easily adjusted by changing the size of the shell-forming particles have been shown. As a proof of concept, like self-assembling macroscopic LEGO bricks, the proposed bottom-up strategy is used to access distinct versatile SCbots, including magnetically guided micro-carriers constructed from Fe3O4 nanoparticles and a “chemistry-on-the-fly” platform for CO2 sequestration constructed from carbonic anhydrase (CA). We report a flexible and universal route to create versatile SCbots with adjustable speeds and navigation capacities, which are in high demand for microrobots in various real applications.