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Microswarms have shown great potential in biomedical applications at small scales due to their features of wireless actuation and collective microrobotic behaviors. However, actuation of microswarms with strong universality and intelligent biomimetic behaviors is always a great challenge. Here, photothermal damage-free actuation of an intelligent microswarm based on light-induced cold Marangoni flow (CMF) is reported, along with collective drug delivery and targeted cell chemotherapy. This microswarm actuation shows strong universality and high controllability for both abiotic particles and living materials. Importantly, this microswarm exhibits intelligent biomimetic behaviors, such as collective migration, size-based self-organization, and group rejection, due to the synergy between cold flow with individual agents. The distinctive photothermal isolation capability of CMF ensures the microswarm to perform photothermal damage-free biomedical tasks such as collective gene delivery and targeted single-cell chemotherapy. This light-induced CMF provides an optical strategy for photothermal damage-free actuation of intelligent biomimetic microswarm robots, with great promises to perform many collective and cognitive tasks in biomedical applications such as cooperative grasping, collective drug delivery, and precise chemotherapy. IntroductionIn the biological world, many individual organisms, such as honeybees, ants, and herrings, can gather together to form swarms, resulting in hierarchical organizational frameworks. [1] Although individual behaviors are governed by relatively simple rules, the communication and interaction of a vast number of individuals allows swarms to be constructed and assembled into various forms. These swarms exhibit complicated collective behaviors and functions, drastically altering how they interact with their surroundings. [2] Similarly, research on artificial microswarms opens many new possibilities for exploring dynamic interactions

Contamination of nano‐biothreats, such as viruses, mycoplasmas, and pathogenic bacteria, is widespread in cell cultures and greatly threatens many cell‐based bio‐analysis and biomanufacturing. However, non‐invasive trapping and removal of such biothreats during cell culturing, particularly many precious cells, is of great challenge. Here, inspired by the wake‐riding effect, a biocompatible opto‐hydrodynamic diatombot (OHD) based on optical trapping navigated rotational diatom (Phaeodactylum tricornutum Bohlin) for non‐invasive trapping and removal of nano‐biothreats is reported. Combining the opto‐hydrodynamic effect and optical trapping, this rotational OHD enables the trapping of bio‐targets down to sub‐100 nm. Different nano‐biothreats, such as adenoviruses, pathogenic bacteria, and mycoplasmas, are first demonstrated to be effectively trapped and removed by the OHD, without affecting culturing cells including precious cells such as hippocampal neurons. The removal efficiency is greatly enhanced via reconfigurable OHD array construction. Importantly, these OHDs show remarkable antibacterial capability, and further facilitate targeted gene delivery. This OHD serves as a smart micro‐robotic platform for effective trapping and active removal of nano‐biothreats in bio‐microenvironments, and especially for cell culturing of many precious cells, with great promises for benefiting cell‐based bio‐analysis and biomanufacturing.