An in situ forming hydrogel has emerged as a promising wound dressing recently. As physically crosslinked hydrogels are normally unstable, most in situ forming hydrogels are chemically cross-linked. However, big concerns have remained regarding the slow gelation and the potential toxicity of residual functional groups from cross-linkers or the polymer matrix. Herein, we report a sprayable in situ forming hydrogel composed of poly(Nisopropylacrylamide 166 -co-n-butyl acrylate 9 )-poly(ethylene glycol)-poly(N-isopropylacrylamide 166 -co-n-butyl acrylate 9 ) copolymer (P(NIPAM 166 -co-nBA 9 )-PEG-P(NIPAM 166 -co-nBA 9 ), denoted as PEP) and silver-nanoparticles-decorated reduced graphene oxide nanosheets (Ag@rGO, denoted as AG) in response to skin temperature. This thermoresponsive hydrogel exhibits intriguing sol−gel irreversibility at low temperatures for the stable dressing of a wound, which is attributed to the inorganic/polymeric dual network and abundant coordination interactions between Ag@rGO nanosheets and PNIPAM. The biocompatibility and antibacterial ability against methicillin-resistant Staphylococcus aureus (MRSA) of this PEP-AG hydrogel wound dressing are confirmed in vitro and in vivo, which could transparently promote the healing of a MRSA-infected skin defect.

Antibacterial efficiency can be effectively improved by applying targeting antibacterial materials and strategies. Herein, the successful synthesis of uniform pH-responsive Ag nanoparticle clusters (AgNCs) is demonstrated, which can collapse and reassemble into nonuniform Ag NPs upon exposure to the acidic microenvironment of bacterial infections. This pH triggered reassembly contributes greatly to the improved antibacterial activities of AgNCs against both methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). The minimum inhibitory concentration and minimum bactericidal concentration against MRSA are as low as 4 and 32 µg mL −1 (which are 8 and 32 µg mL −1 for E. coli), respectively. In vivo skin wound healing experiments confirm AgNCs can serve as an effective wound dressing to accelerate the healing of MRSA infection. The development of responsive AgNCs offers new materials and strategies in targeting antibacterial applications.

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An anti-biofouling double layered GCZ scaffold is fabricated as a long-term stable solar-driven steam generation device in bacteria-containing actual environment.

The abuse of antibiotics resulted in the emergence of antibiotics-resistant bacteria, which has raised a great social concern together with the impetus to develop effective antibacterial materials. Herein, the synthesis of biocompatible enzyme-responsive Ag nanoparticle assemblies (ANAs) and their application in the high-efficiency targeted antimicrobial treatment of methicillin-resistant Staphylococcus aureus (MRSA) have been demonstrated. The ANAs could collapse and undergo stable/collapsed transition on approaching MRSA because of the serine protease-like B enzyme proteins (SplB)-triggered decomposition of the branched copolymers which have been employed as the macrotemplate in the synthesis of responsive ANAs. This transition contributed greatly to the high targeting affinity and efficiency of ANAs to MRSA. The minimum inhibitory concentration and minimum bactericidal concentration against MRSA were 2.0 and 32.0 μg mL–1, respectively. Skin wound healing experiments confirmed that the responsive ANAs could serve as an effective wound dressing to accelerate the healing of MRSA infection.

The ever-growing global crisis of multidrug-resistant bacteria has triggered a tumult of activity in the design and development of antibacterial formulations. Here, atomically thin antimony selenide nanosheets (Sb2Se3 NSs), a minimal-toxic and low-cost semiconductor material, were explored as a high-performance two-dimensional (2D) antibacterial nanoagent via a liquid exfoliation strategy integrating cryo-pretreatment and polyvinyl pyrrolidone (PVP)-assisted exfoliation. When cultured with bacteria, the obtained PVP-capped Sb2Se3 NSs exhibited intrinsic long-term antibacterial capability, probably due to the reactive oxygen species generation and sharp edge-induced membrane cutting during physical contact between bacteria and nanosheets. Upon near-infrared laser irradiation, Sb2Se3 NSs achieved short-time hyperthermia sterilization because of strong optical absorption and high photothermal conversion efficiency. By virtue of the synergistic effects of these two broad-spectrum antibacterial mechanisms, Sb2Se3 NSs exhibited high-efficiency inhibition of conventional Gram-negative Escherichia coli, Gram-positive methicillin-resistant Staphylococcus aureus, and wild bacteria from a natural water pool. Particularly, these three categories of bacteria were completely eradicated after being treated with Sb2Se3 NSs (300 μM) plus laser irradiation for only 5 min. In vivo wound healing experiment further demonstrated the high-performance antibacterial effect. In addition, Sb2Se3 NSs depicted excellent biocompatibility due to the biocompatible element constitute and bioinert PVP modification. This work enlightened that atomically thin Sb2Se3 NSs hold great promise as a broad-spectrum 2D antibacterial nanoagent for various pathogenic bacterial infections.

Here we reported a residue-free green nanotechnology which synergistically enhance the pesticides efficiency and successively eliminate its residue. We built up a composite antifungal system by a simple pre-treating and assembling procedure for investigating synergy. Investigations showed 0.25 g/L ZnO nanoparticles (NPs) with 0.01 g/L thiram could inhibit the fungal growth in a synergistic mode. More importantly, the 0.25 g/L ZnO NPs completely degraded 0.01 g/L thiram under simulated sunlight irradiation within 6 hours. It was demonstrated that the formation of ZnO-thiram antifungal system, electrostatic adsorption of ZnO NPs to fungi cells and the cellular internalization of ZnO-thiram composites played important roles in synergy. Oxidative stress test indicated ZnO-induced oxidative damage was enhanced by thiram that finally result in synergistic antifungal effect. By reducing the pesticides usage, this nanotechnology could control the plant disease economically, more significantly, the following photocatalytic degradation of pesticide greatly benefit the human social by avoiding negative influence of pesticide residue on public health and environment.

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