Electrospun nanofibrous membranes meet antibacterial nanomaterials:From preparation strategies to biomedical applications

Electrospun nanofibrous membranes(eNFMs)have been extensively developed for bio-applications due to their structural and compositional similarity to the natural extracellular matrix.However,the emergence of antibiotic resistance in bacterial infections significantly impedes the further development and applications of eNFMs.The development of antibacterial nanomaterials substantially nourishes the engineering design of antibacterial eNFMs for combating bacterial infections without relying on antibiotics.Herein,a comprehensive review of diverse fabrication techniques for incorporating antibacterial nanomaterials into eNFMs is presented,encompassing an exhaustive introduction to various nanomaterials and their bactericidal mechanisms.Furthermore,the latest achievements and breakthroughs in the application of these antibacterial eNFMs in tissue regenerative therapy,mainly focusing on skin,bone,periodontal and tendon tissues regeneration and repair,are systematically summarized and discussed.In particular,for the treatment of skin infection wounds,we highlight the antibiotic-free antibacterial therapy strategies of antibacterial eNFMs,including(i)single model therapies such as metal ion therapy,chemodynamic therapy,photothermal therapy,and photodynamic therapy;and(ii)multimodel therapies involving arbitrary combinations of these single models.Additionally,the limitations,challenges and future opportunities of antibacterial eNFMs in biomedical applications are also discussed.We anticipate that this comprehensive review will provide novel insights for the design and utilization of antibacterial eNFMs in future research.

Antibacterial Effects of Nanometallic Materials in Genetic Transformation of Anthurium by Agrobacterium-mediated Method

[Objective] This study was conducted to investigate the application of nanometallic materials in inhibiting Agrobacteriurn contamination in genetic transformation of Anthurium. [Method] Different nanometallic materials were added into Agrobacterium medium and Anthurium callus medium, to investigate the effects of their effects on Agrobacterium growth, callus growth and differentiation, and Agrobacterium contamination. [Result] Among the 4 nanometallic materials, NanoAg-2 showed a significant inhibitory effect on the growth of Agrobacterium, with a minimal inhibitory concentration of 25 mg/L. Even for the Anthurium calli or transgenic material contaminated by the Agrobacterium, a good antibacterial effect could be achieved after treating with 25 mg/L NanoAg-2 for 1 d with oscillation, the antibacterial rate reached 100%, and the Anthurium calli could grow and differentiate normally. [Conclusioa] NanoAg-2 could effectively inhibit Agrobacterium contamination, and its an- tibacterial effect is significantly better than cephalosporin and carbenicillin.

Efficient elimination of multidrug-resistant bacteria using copper sulfide nanozymes anchored to graphene oxide nanosheets

Antibacterial nanomaterials have attracted growing interest for bacterial infection therapy.However,most nanomaterials eliminate bacteria either physically or chemically,which hampers their efficacy when dealing with multidrug-resistant bacteria.To overcome this,we integrated copper sulfide(CuS)nanoparticles with active graphene oxide nanosheets(GO NSs)to synthesize a superior nanocomposite(CuS/GO NC)that acts both physically and chemically on the bacteria.CuS/GO NC was produced using a facile hydrothermal method,whereby the CuS nanoparticles grew and were uniformly dispersed on the GO NSs in situ.We found that the CuS/GO NC possesses a unique needle-like morphology that physically damages the bacterial cell membrane.CuS/GO NC also exhibits high oxidase-and peroxidase-like activity,ensuring efficient generation of the reactive oxygen species•OH from H2O2,which kills bacteria chemically.These features endow the CuS/GO NC with excellent antibacterial capabilities to kill multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus(MRSA)with only a single dose.Additionally,it was found that the CuS/GO NC accelerated the healing of infected wounds in vivo owing to its good biocompatibility as well as facilitation of cell migration and collagen secretion.This study provides a new strategy to combine the physical and chemical antibacterial modes of nanomaterials to develop more effective therapies to combat multidrug-resistant bacterial infections.