In situ preparation of silver nanoparticle embedded composite nanofibrous membrane: a multi-layered biocidal air filter

Deteriorating air quality has increased the need for designing composite integrated nanofibrous membranes, which are suitable for facemask technology providing efficient solution against microbial propagation and particulate matter. Through this research work, an aramid-based multilayered membrane is developed which provides significantly increased mechanical stability when compared to easily collapsing nanofibrous structures usually considered for air filtration applications. The developed filter is tested for its bacterial filtration efficiency through an Andersen sampler using Staphylococcus aureus as the challenge aerosol with mean particle size of 3.0 +/- 0.3 mu m. The Particulate Matter (with diameters ranging from 0.3 to 10 mu m) filtration efficiency and Bacterial filtration efficiency of 99.41% and 99.51% was achieved, respectively, indicating its potential for applications ranging from facemasks (mainly for protection against airborne microorganisms) to industrial-scale air filters. Our study indicated that the combination of silver nanoparticles incorporated polyacrylonitrile nanofibers integrated with a layer of aramid based coaxial nanofibers offer a new strategy to construct advanced multifunctional membrane which could not only perform well as an antimicrobial filter but also remove particulate matter in air effectively.