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[Display omitted] Titanium (Ti) was an excellent medical metal material, but the lack of good antibacterial activity confined its further practical application. To solve this dilemma, a coating containing graphene oxide (GO) and copper (Cu) was prepared on the surface of Ti sheet (Ti/APS/GO/Cu). First, physical sterilization could be carried out through the sharp-edged sheet structure of GO. Second, the oxygen-containing functional group on the surface of GO and the released Cu2+ would generate reactive oxygen species for chemical sterilization. The synergistic effect of GO and Cu substantially enhanced the in vitro and in vivo antibacterial property of Ti sheet, thereby reducing bacterial-related inflammation. Quantitatively, the antibacterial rate of Ti/APS/GO/Cu against E. coli or S. aureus reached over 99%. Besides, Ti/APS/GO/Cu showed excellent biocompatibility and no toxicity to cell. Such work developed multiple sterilization avenues to design non-antibiotic, safe and efficient antibacterial implant material for the biomedical domain. [ABSTRACT FROM AUTHOR]

An injectable, highly biocompatible AgNC-reinforced hydrogel with synergistic antibacterial capability is fabricated, which can mediate the ROS balance to ameliorate oxidative stress, promote collagen deposit to facilitate re-epithelization, and significantly accelerate the infection-impaired wound healing. [Display omitted] Clinical application of antibiotic-free agents like silver nanoparticle-derived materials remains a critical challenge due to their limited long-term antibacterial activity and potential system toxicity. Herein, a highly biocompatible Ag nanocluster-reinforced hydrogel with enhanced synergistic antibacterial ability has been developed. Specifically, bioactive curcumin was incorporated into lysozyme-protected ultrasmall Ag nanoclusters (LC-AgNCs) and further integrated with sodium alginate (Sa) hydrogel (LC-AgNCs@Sa) through multiple interaction forces. Due to the synergistic antibacterial activity, LC-AgNCs could effectively kill both S. aureus and E. coli bacteria with a concentration down to 2.5 μg mL−1. In-depth mechanism investigations revealed that the bactericidal effect of LC-AgNCs lies in their bacterial membrane destruction, reactive oxygen species (ROS) production, glutathione depletion and prooxidant-antioxidant system disruption ability. Curcumin can mediate the intracellular ROS balance to protect NIH 3T3 cells from oxidative stress and improve the biocompatibility of LC-AgNCs@Sa. LC-AgNCs@Sa with long-term antibacterial ability can effectively protect the wound from bacterial invasion in vivo , and significantly accelerate the wound healing process due to their distinctive functions of inhibiting inflammatory factor (TNF-α) production, promoting collagen deposit and facilitating re-epithelization. This study provides a new, versatile strategy for the design of high-performance antibacterial dressing for broad infectious disease therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] Enhancing long-term antibacterial activity of membrane materials is an effective strategy to reduce biological contamination. Herein, we developed a long-term, synergistic antibacterial polyacrylonitrile (PAN) nanofiber membrane by a "one-pot" electrospinning process. In the reaction solution of PAN and N, N -dimethylformamide (DMF), silver-silicon dioxide nanoparticles (Ag@SiO 2 NPs) are in-situ synthesized and stabilized using silane coupling agent; and [2-(methacryloyloxy)-ethyl] trimethylammonium chloride (MT) monomers are then in-situ cross-linked to obtain a polyquaternary ammonium salt (PMT). Subsequently, the casting solution is directly used to fabricate Ag@SiO 2 /PMT-PAN nanofibrous membrane (NFM) via electrospinning. The antibacterial activity, reusability, synergy effect and biological safety of the Ag@SiO 2 /PMT-PAN NFM are systematically investigated, and the synergistic antibacterial mechanism is also explored. Even at very low (0.3 wt%) content of silver, the Ag@SiO 2 /PMT-PAN NFM exhibits excellent antibacterial activity against E. coli (99%) and S. aureus (99%). Also, the antibacterial ability of the NFM remains the same level after three cycles of antibacterial processes with the efficient synergy effects of Ag@SiO 2 and PMT components. When the Ag@SiO 2 /PMT-PAN contacts with bacteria, the PMT attracts and kills the bacteria through electrostatic action. The bacteria with damaged cell membranes are deposited on the nanofibrous membrane, which could greatly promote the release of Ag+ and further enhance the antibacterial activity. Moreover, L929 fibroblasts are co-cultured with the extract of 4 mg/mL Ag@SiO 2 /PMT-PAN for 5 days, which exhibits a low cytotoxicity with a cell proliferation ratio of 95%. This work opens new pathways for developing long-term effective and synergistic antibacterial nanofibrous membrane materials to prevent infections associated with biomedical equipment. [ABSTRACT FROM AUTHOR]

Sucrose laurate (SL) is a dual-functional additive with emulsifying and antibacterial activities. The synergistic antibacterial mechanism of SL and nisin were studied against Staphylococcus aureus. Alkaline phosphatase and peptidoglycan assays showed that SL and nisin could synergistically disrupt the integrity of cell wall by blocking the synthesis of peptidoglycan. Fluorescence spectroscopy and flow cytometry analysis revealed that SL and nisin synergistically depolarized the membrane potential, inhibited the Na+K+ and Ca2+Mg2+-ATPase activities on cell membrane, triggered K+ leakage, and damaged the permeability and integrity of cell membrane. SEM and TEM observations further exhibited obvious morphological changes, structural disruption and cytoplasmic leakage. Gel retardation and fluorescence spectroscopy analysis suggested that SL and nisin synergistically influenced the protein and genomic DNA. Finally, the synergistic preservative effect of SL and nisin was evidenced in real food system of milk beverage. This research could provide the insights into broadening the application of SL in food industry. • SL as a bifunctional additive shows synergistic antibacterial effect with nisin against S. aureus. • The synergistic antibacterial mechanism was elucidated from multiple targets. • The synergistic preservative effect of SL and nisin was evidenced in milk beverage. • This study could provide evidence to broaden the application of SL in food industry. [ABSTRACT FROM AUTHOR]