Electrospun PVB/AVE NMs as mask filter layer for win-win effects of filtration and antibacterial activity.

The COVID-19 pandemic has caused serious social and public health problems. In the field of personal protection, the facial masks can prevent infectious respiratory diseases, safeguard human health, and promote public safety. Herein, we focused on preparing a core filter layer for masks using electrospun polyvinyl butyral/apocynum venetum extract nanofibrous membranes (PVB/AVE NMs), with durable interception efficiency and antibacterial properties. In the spinning solution, AVE acted as a salt to improve electrical conductivity, and achieve long-lasting interception efficiency with adjustable pore size. It also played the role of an antibacterial agent in PVB/AVE NMs to achieve win-win effects. The hydrophobicity of PVB-AVE-6% was 120.9° whereas its filterability reached 98.3% when the pressure drop resistance was 142 Pa. PVB-AVE-6% exhibited intriguing properties with great antibacterial rates of 99.38% and 98.96% against S. aureus and E. coli, respectively. After a prolonged usability test of 8 h, the filtration efficiency of the PVB/AVE masks remained stable at over 97.7%. Furthermore, the antibacterial rates of the PVB/AVE masks on S. aureus and E. coli were 96.87% and 96.20% respectively, after using for 2 d. These results indicate that PVB/AVE NMs improve the protective performance of ordinary disposable masks, which has certain application in air filtration.

Future antiviral polymers by plasma processing.

Coronavirus disease 2019 (COVID-19) is largely threatening global public health, social stability, and economy. Efforts of the scientific community are turning to this global crisis and should present future preventative measures. With recent trends in polymer science that use plasma to activate and enhance the functionalities of polymer surfaces by surface etching, surface grafting, coating and activation combined with recent advances in understanding polymer-virus interactions at the nanoscale, it is promising to employ advanced plasma processing for smart antiviral applications. This trend article highlights the innovative and emerging directions and approaches in plasma-based surface engineering to create antiviral polymers. After introducing the unique features of plasma processing of polymers, novel plasma strategies that can be applied to engineer polymers with antiviral properties are presented and critically evaluated. The challenges and future perspectives of exploiting the unique plasma-specific effects to engineer smart polymers with virus-capture, virus-detection, virus-repelling, and/or virus-inactivation functionalities for biomedical applications are analysed and discussed.