Micro-Bio-Chemo-Mechanical-Systems: Micromotors, Microfluidics and Nanozymes for Biomedical Applications

Tetherless nano/-micromotors powered by chemical reactions and/or external fields generate motive forces and perform biomedical tasks, such as delivery of cargo payloads, minimally-invasive surgery, deactivation of pathogens and isolation of cancer cells. Micromotors can significantly expand short-range dynamic responses of passive biomedical micro-carriers, however, several major challenges, including biocompatibility, biodegradability, biochemical reactions as a fuel, deep tissue imaging methods must be addressed before micromotors can be translated into clinical uses. Nanozymes are nanomaterials that display enzyme-like characteristics (e.g., catalase, oxidase, peroxidase, superoxide dismutase) and represent a potentially revolutionary way to interconnect catalytic reactions, micromotors and biological systems. Today, a convergence of nanozymes and micromotors with microfluidics can lead to a paradigm shift in the fabrication of micro/-emulsions, drops, capsules and bubbles in reasonable quantities, encapsulation of sub-systems and shell-core engineering with desired tuneable biological, physical, chemical and mechanical properties. Additional functionalization methods, such as Layer-by-Layer assembly, can be used as a basis for multimodality of micro/-bubbles and capsules with a combination of ultrasound, optoacoustic, fluorescent, magnetic resonance imaging modalities, and desired surface properties. This review aims are to discuss recent achievements, challenges, and opportunities of micromotors, nanozymes, and microfluidics, which originated as separate disciplines and currently can be combined towards development of advanced Micro-Bio-Chemo-Mechanical-Systems for diverse bio-applications.