The topographic features of an implant, which mechanically regulate cell behaviors and functions, are critical for the clinical success in tissue regeneration. How cells sense and respond to the topographical cues, e.g., interfacial roughness, is yet to be fully understood and even debatable. Here, the mechanotransduction and fate determination of human mesenchymal stem cells (MSCs) on surface roughness gradients are systematically studied. The broad range of topographical scales and high‐throughput imaging is achieved based on a catecholic polyglycerol coating fabricated by a one‐step‐tilted dip‐coating approach. It is revealed that the adhesion of MSCs is biphasically regulated by interfacial roughness. The cell mechanotransduction is investigated from focal adhesion to transcriptional activity, which explains that cellular response to interfacial roughness undergoes a direct force‐dependent mechanism. Moreover, the optimized roughness for promoting cell fate specification is explored.

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The recently emerging metal-air batteries equipped with advanced oxygen electrodes have provided enormous opportunities to develop the next generation of wearable and bio-adaptable power sources. Theoretically, neutral electrolyte-based Mg-air batteries possess potential advantages in electronics and biomedical applications over the other metal-air counterparts, especially the alkaline-based Zn-air batteries. However, the rational design of advanced oxygen electrode for Mg-air batteries with high discharge voltage and capacity under neutral conditions still remains a major challenge. Inspired by fibrous string structures of bufo-spawn, it is reported here that the scalable synthesis of atomic Fe-N coupled open-mesoporous N-doped-carbon nanofibers (OM-NCNF-FeN ) as advanced oxygen electrode for Mg-air batteries. The fabricated OM-NCNF-FeN electrodes present manifold advantages, including open-mesoporous and interconnected structures, 3D hierarchically porous networks, good bio-adaptability, homogeneously coupled atomic Fe-N sites, and high oxygen electrocatalytic performances. Most importantly, the assembled Mg-air batteries with neutral electrolytes reveal high open-circuit voltage, stable discharge voltage plateaus, high capacity, long operating life, and good flexibility. Overall, the discovery on fabricating atomic OM-NCNF-FeN electrode will not only create new pathways for achieving flexible, wearable, and bio-adaptable power sources, but also take a step towards the scale-up production of advanced nanofibrous carbon electrodes for a broad range of applications.

Recent emerged antibacterial agents provide enormous new possibilities to replace antibiotics in fighting bacterial infectious diseases. Although abundant types of nanoagents are developed for preventing pathogen colonization, however, rationally design of nonchemotherapic, robust, and clinical‐adaptable nanoagents with tunable bacterial trap and killing activities remains a major challenge. Here, a demonstration of controlling the trap, ablation, and release activities of pathogenic bacteria via stimulus‐responsive regulatory mechanism is reported. First, temperature‐sensitive polymer brush is chemically grown onto carbon nanotube–Fe3O4, whereby the synthesized nanoagents can transfer from hydrophilic dispersion to hydrophobic aggregation upon near‐infrared light irradiation, which thus controls the bacterial trap, killing, and detaching. In turn, the formed aggregations will serve as localized heating sources to enhance photothermal ablation of bacteria. Systematically antibacterial experiments and mouse wound disinfection demonstrate the ultrarobust and recyclable disinfection capability of nanoagents with nearly 100% killing ratio to Staphylococcus aureus. Overall, for the first time, we represent a pioneering study on designing nonchemotherapic and robust dual‐responsive nanoagents that can sensitively and reversibly trap, inactivate, and detach bacteria. We envision that such nanoagents will not only have potential applications in pathogenic bacteria prevention but also provide a new pathway for wound disinfection, implant sterilization, and also live bacteria transportation.

Recently emerging graphene-based 2D nanoplatforms with multiple therapeutic modalities provide enormous opportunities to combat pathogenic bacterial infections. However, because these materials suffer from complicated synthesis, massive dosage requirements, and abundant nonlocalized heat, much more simplified, tunable, and localized eradication approaches are urgently required. Herein, we report on the fabrication of the metal−organic-framework (MOF)-derived 2D carbon nanosheets (2D-CNs) with phase-to-size transformation and localized bacterial eradication capabilities for augmented anti-infective therapy. The MOFderived, ZnO-doped carbon on graphene (ZnO@G) is first synthesized and then anchored with phase transformable thermally responsive brushes

Severe infectious diseases caused by pathogenic bacteria have become urgent threats to global public health. Antibacterial materials with combined chemophotothermal therapeutic capabilities possess distinct advantages when compared with many other antibacterial approaches. However, developing simplified and chemically tunable precursors to synthesize such antibacterial nanoagents for rapidly, safely, and synergistically combating pathogenic bacteria remains a huge challenge. Herein, metal-organic framework (MOF)-derived nanocarbons with near-infrared (NIR)-responsive and sizetransformable capabilities are designed to overcome this challenge. The MOF-derived nanocarbons with chemo-photothermal bactericidal capabilities are first synthesized, and then coated with a thermoresponsive gel layer to obtain ON-OFF switching capability for bacterial trapping. The fabricated nanocarbons exhibit high photo-to-thermal conversion efficiency and fast size transformation from nanodispersions to micrometer aggregations upon NIR irradiation, thus enabling nanocarbons to generate localized massive heat and abundant Zn 2+ ions for directly disrupting bacterial membrane and intracellular proteins. Furthermore, these nanocarbons not only exhibit a nearly 100% bactericidal ratio at very low dosage, but also possess highly efficient and safe wound disinfection activities, which are comparable to vancomycin. Overall, these proposed novel nanocarbons display robust and localized chemo-photothermal bactericidal capability and possess great potential to be used as alternative to antibiotics for broad-spectrum eradication of pathogenic bacteria.

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SARS-CoV-2 poses a major threat to the public health worldwide, as it causes a respiratory disease named COVID-19. Since the first case report in December 2019, a pandemic ensued with approximately one million deaths within the first nine months. [1] SARS-CoV-2 belongs to the beta-coronavirus genus. All coronaviruses have a lipid envelope with a capsid, which encapsulates the helical nucleocapsid with the RNA genome. [2] The most prominent viral envelope component is the spike glycoprotein (S), which interacts with the angiotensin-converting enzyme 2 (ACE2) on the surface of host cells and initiates virus entry, the first step of the SARS-CoV-2 infection cycle. [1,3-5] Moreover, the polybasic cleavage site of S is found to play a crucial role in the binding between the virus and ACE2. [6] Numerous efforts have been devoted to development of vaccines that generate neutralizing antibodies toward S to block viral interaction with Search of new strategies for the inhibition of respiratory viruses is one of the urgent health challenges worldwide, as most of the current therapeutic agents and treatments are inefficient. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic and has taken lives of approximately two million people to date. Even though various vaccines are currently under development, virus, and especially its spike glycoprotein can mutate, which highlights a need for a broad-spectrum inhibitor. In this work, inhibition of SARS-CoV-2 by graphene platforms with precise dual sulfate/alkyl functionalities is investigated. A series of graphene derivatives with different lengths of aliphatic chains is synthesized and is investigated for their ability to inhibit SARS-CoV-2 and feline coronavirus. Graphene derivatives with long alkyl chains (>C9) inhibit coronavirus replication by virtue of disrupting viral envelope. The ability of these graphene platforms to rupture viruses is visualized by atomic force microscopy and cryogenic electron microscopy. A large concentration window (10 to 100-fold) where graphene platforms display strongly antiviral activity against native SARS-CoV-2 without significant toxicity against human cells is found. In this concentration range, the synthesized graphene platforms inhibit the infection of enveloped viruses efficiently, opening new therapeutic and metaphylactic avenues against SARS-CoV-2. The ORCID identification number(s) for the author(s) of this article can be found under