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Constructing safe and effective antibacterial surfaces has continuously received great attention, especially in healthcare-related fields. Bioinspired mechano-bactericidal nanostructure surfaces could serve as a promising strategy to reduce surface bacterial contamination while avoiding the development of antibiotic resistance. Although effective, these nanostructure surfaces are prone to be contaminated by the accumulation of dead bacteria, inevitably compromising their long-term antibacterial activity. Herein, a bioinspired nanopillar surface with both mechano-bactericidal and releasing actions is developed, via grafting zwitterionic polymer (poly(sulfobetaine methacrylate) (PSBMA)) on ZnO nanopillars. Under dry conditions, this nanopillar surface displays remarkable mechano-bactericidal activity, because the collapsed zwitterionic polymer layer makes no essential influence on nanopillar structure. Once being incubated with aqueous solution, the surface could readily detach the killed bacteria and debris, owing to the swelling of the zwitterionic layer. Consequentially, the surface antibacterial performances can be rapidly and controllably switched between mechano-bactericidal action and bacteria-releasing activity, guaranteeing a long-lasting antibacterial performance. Notably, these collaborative antibacterial behaviors are solely based on physical actions, avoiding the risk of triggering bacteria resistance. The resultant nanopillar surface also enjoys the advantages of substrate-independency and good biocompatibility, offering potential antibacterial applications for biomedical devices and hospital surfaces. [Display omitted] • A bioinspired nanopillar surface (ZnO-PSBMA) was designed. • ZnO-PSBMA played switchable mechano-bactericidal and releasing actions. • These antibacterial behaviors were solely based on physical actions, avoiding the risk of triggering bacteria resistance. • ZnO-PSBMA nanopillar showed substrate-independency and good biocompatibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • The SMPP surface with accurately and rapidly tunable adhesion was developed. • The sliding angle (SA) achieved in situ transition between ultra-low SA of ∼3° and ultra-high SA of ∼180°. • Even after severe cutting or abrasion, the surface still maintained good functionality. • The SMPP enhanced spatiotemporal droplet manipulation and multiple chemical microreaction. • The designed SMPP platform can be used as an antigravity device for continuous droplet transport. Controlled liquid adhesion behaviors on super-wetting surfaces have gained significant attention, however, precise controlling of adhesion behavior is extremely hard to realize due to some inherent limitation in surface chemistry or morphology. Herein, we report a silicone-oil-infused magnetic porous polydimethylsiloxane (SMPP) surface with magnetically tunable super-wetting behaviors. Benefiting from the magnetic-field-responsive structure and interconnected porous characteristics, the SMPP can use magnetic field to control the seepage and absorption of silicone oil in the micropore channels, thereby precisely changing the adhesion of the water droplets on the surface. Compared to conventional super-wetting surfaces, this SMPP surface displays reversible in-situ conversion from ultra-high to ultra-low droplet adhesion with sliding angles ranging from 3° to 180° that hold up well even after severe cutting or abrasion. We also demonstrated that this tunable adhesion behavior can be used not only to enhance droplet manipulation in spatiotemporal but also to design unique microfluidic microreactors and antigravity transport devices. We envision that this proof-in-concept surface can serve as an important component of integrated control systems for intelligent manipulators, biochemical reactions, fluid transport, and biomedical analysis. [ABSTRACT FROM AUTHOR]