Hydro electroactive Cu/Zn coated cotton fiber nonwovens for antibacterial and antiviral applications.

In this study, Cu/Zn galvanic electrodes were sputtered on the two surfaces of hydrophilic cotton fiber nonwovens (Cotton) to prepare hydro electroactive Cu/Cotton/Zn composites. When the Cu/Cotton/Zn was used as a functional layer in the face mask, the Cu/Zn galvanic electrodes can be spontaneously activated by water vapor molecules exhaled by the human body and generate galvanic current. Based on this, the hydro electroactive Cu/Cotton/Zn demonstrated excellent antibacterial activity against Escherichia coli and Staphylococcus aureus and could deactivate Enterovirus 71 (EV71) virions transmitted through the respiratory tract by 97.72% after 15 min of contact. Moreover, the Cu/Cotton/Zn did not affect the particle filtration efficiency and breathability of the face mask's polypropylene (PP) melt-blown layer. Furthermore, the cytotoxicity assessment of Cu/Cotton/Zn showed no cytotoxicity, indicating good biological security. Overall, the Cu/Cotton/Zn may provide a new approach to increase the antibacterial and antiviral performance of current personnel protective equipment on the market.

State-of-the-art review of advanced electrospun nanofiber yarn-based textiles for biomedical applications.

The pandemic of the coronavirus disease 2019 (COVID-19) has made biotextiles, including face masks and protective clothing, quite familiar in our daily lives. Biotextiles are one broad category of textile products that are beyond our imagination. Currently, biotextiles have been routinely utilized in various biomedical fields, like daily protection, wound healing, tissue regeneration, drug delivery, and sensing, to improve the health and medical conditions of individuals. However, these biotextiles are commonly manufactured with fibers with diameters on the micrometer scale (> 10 µm). Recently, nanofibrous materials have aroused extensive attention in the fields of fiber science and textile engineering because the fibers with nanoscale diameters exhibited obviously superior performances, such as size and surface/interface effects as well as optical, electrical, mechanical, and biological properties, compared to microfibers. A combination of innovative electrospinning techniques and traditional textile-forming strategies opens a new window for the generation of nanofibrous biotextiles to renew and update traditional microfibrous biotextiles. In the last two decades, the conventional electrospinning device has been widely modified to generate nanofiber yarns (NYs) with the fiber diameters less than 1000 nm. The electrospun NYs can be further employed as the primary processing unit for manufacturing a new generation of nano-textiles using various textile-forming strategies. In this review, starting from the basic information of conventional electrospinning techniques, we summarize the innovative electrospinning strategies for NY fabrication and critically discuss their advantages and limitations. This review further covers the progress in the construction of electrospun NY-based nanotextiles and their recent applications in biomedical fields, mainly including surgical sutures, various scaffolds and implants for tissue engineering, smart wearable bioelectronics, and their current and potential applications in the COVID-19 pandemic. At the end, this review highlights and identifies the future needs and opportunities of electrospun NYs and NY-based nanotextiles for clinical use.