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Chemotaxis plays a crucial role in the realization of various functions of human life such as fertilization, immune function, inflammatory response, regeneration processes, etc. Inspired by the natural chemotaxis, colloidal motors with chemotactic ability can realize intelligent sense and targeted navigation, which bring a revolutionary method to biomedical applications like precision medicine. However, the application in the biomedical field requires the colloidal motors with submicrometer scale, strong chemotactic ability and clear chemotactic mechanism. In this Concept article, we introduce the recent progress of chemotactic colloidal motors, covering the fundamental theory behind experimental advancements. Particularly, the torque‐driven reorientation motion of the submicrometer‐sized colloidal motors during chemotaxis is discussed, and also their underlying mechanism is proposed. With the continuous research on chemotactic colloidal motors, it is believed that the emerging chemotactic colloidal motors will broaden practical applications in the biomedical field. [ABSTRACT FROM AUTHOR]

We report a direct experimental observation of the torque‐driven active reorientation of glucose‐fueled flasklike colloidal motors to a glucose gradient exhibiting a positive chemotaxis. These streamlined flasklike colloidal motors are prepared by combining a hydrothermal synthesis and a vacuum infusion and can be propelled by an enzymatic cascade reaction in the glucose fuel. Their flasklike architecture can be used to recognize their moving posture, and thus the dynamic glucose‐gradient‐induced alignment and orientation‐dependent motility during positive chemotaxis can be examined experimentally. The chemotactic mechanism is that the enzymatic reactions inside lead to the glucose acid gradient and the glucose gradient which generate two phoretic torques at the bottom and the opening respectively, and thus continuously steer it to the glucose gradient. Such glucose‐fueled flasklike colloidal motors resembling the chemotactic capability of living organisms hold considerable potential for engineering active delivery vehicles in response to specific chemical signals. [ABSTRACT FROM AUTHOR]

We report robust control over the dynamic assembly, disassembly, and reconfiguration of light‐activated molybdenum disulfide (MoS2) colloidal motor swarms with features not possible in equilibrium systems. A photochemical reaction produces chemical gradients across the MoS2 colloidal motors to drive them to move. Under illumination of a gradient light, these colloidal motors display a positive phototactic motion. Mesoscale simulations prove that the self‐diffusiophoresis induced by the locally consumed oxygen gradient across MoS2 colloidal motors dominates the phototactic process. By programming the structured illumination, the collective migration and well‐defined shapes of colloidal motor swarms can be externally regulated. The successful realization of programmable swarm transformation of colloidal motors like the emergent behaviors of living systems in nature provides a direct proof‐of‐concept for active soft materials and systems, with adaptive and interactive functions. [ABSTRACT FROM AUTHOR]