Domino Reaction Encoded Heterogeneous Colloidal Microswarm with On-Demand Morphological Adaptability.

Emulating natural swarm intelligence with group-level functionality in artificial micro/nanorobotic systems offers an opportunity to sublimate the limited functions of individuals and revolutionize their applications. However, achieving synchronous operation of microswarms with environmental adaptability and cooperative tasking capability remains a challenge. Here, an adaptive and heterogeneous colloidal magnetic microswarm with domino reaction encoded cooperative functions is presented. Through programming external magnetic fields, the system self-organizes into two swarm states, that is, vortex and ribbon microswarms, which can switch between each other reversibly within seconds, allowing to traverse tortuous, branched, and confined environments through adaptive morphological transformation. By specializing subgroups of building blocks with separate functions, cooperative tasking capability is integrated into the heterogeneous system following a "division of labor" manner. Given targeted therapy as a proof-of-concept task, the coordinated delivery of heterogeneous colloidal system across a complex environment with an access rate higher than 90% is demonstrated, and the specialization and cooperation between building blocks to disrupt multiple growth pathways of cancer cells via domino reaction are realized. The reconfigurable microswarm with hierarchical functionality presents a bioinspired approach to adapt to environmental variations and address multitasking requirements, which advances the development of microrobotic swarms and promises major benefits in biomedical fields.