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Utilization of electro‐responsive biomaterials with antibacterial properties is advantageous for facilitating septic wound healing and tissue regeneration. However, the dose‐response effects of electrical stimuli from these materials against bacteria are not rigorously characterized, and achieving synergy of bactericidal and pro‐regenerative effects of biomaterials remains a major challenge. Here, a graded series of flexible BaTiO3/P(VDF‐TrFE) electroactive nanocomposite membranes (EMs) are developed with varying surface charge intensities, to serve as antibacterial dressing for septic wound healing. EMs display broad‐spectrum antibacterial effects against both Gram‐positive and Gram‐negative bacteria in a dose‐dependent manner, depending on the magnitude of their surface electrical potential. Mechanistically, the surface charge of EMs increase intracellular levels of reactive oxygen species within bacteria cells, which in turn caused oxidative damage to the bacterial membrane, thereby suppressing bacterial activity and biofilm formation. Moreover, in vivo studies demonstrated that EMs effectively inhibited S. aureus infection and accelerated wound healing in a mouse skin defect model, as well as ameliorated P. gingivalis‐mediated periodontal inflammation in a mouse periodontitis model. Hence, this study optimizes the antibacterial properties of electroactive materials and characterizes the dose‐response effects of surface electrical charge against bacteria, thus validating the therapeutic applications of electroactive biomaterials in combating bacterial infection. [ABSTRACT FROM AUTHOR]

Artificial microswarms with a collective intelligence that can execute cooperative tasks will serve as intelligent micro/nanorobot systems for many biomedical and microengineering applications. However, it remains challenging to construct microswarms with 3D dynamic and reconfigurable structures that can execute complex spatiotemporal‐dependent tasks. Here, simply using a tapered optical fiber (TOF) with 1.55 µm wavelength light irradiation, a convenient opto‐hydrodynamic strategy for 3D dynamic microswarm actuation based on photothermal gradient‐induced Marangoni effect is reported. With light irradiation at the water‐air interface, randomly distributed microparticles are reorganized into firework‐like 3D swarms with four petals. Such petals in the microswarm are controllably reconfigurable by adjusting the angle between TOF and water‐air interface. These microswarms are also deformable and capable of performing stable migration by simply moving the TOF. Importantly, this opto‐hydrodynamic strategy is applicable for the formation of artificial 3D‐dynamic bio‐microswarms using different biological cells, which further facilitate the regulation of biological processes such as bacteria growth/division. This opto‐hydrodynamic strategy provides a new solution for 3D dynamic microswarm formation, with many potentials for biomedical and microengineering applications that need spatiotemporal‐dependent individual cooperation. [ABSTRACT FROM AUTHOR]