De‐Novo Designed Antibacterial N95 Facial Mask: Comprising a Nano‐Garden Using ZnO Nanoflower

ABSTRACT Nowadays the N95 facial mask has gained huge attention due to COVID19 pandemic situation and it serves as the prime PPE. Though the microbes can be restricted to get inside the human body due to the presence of mask temporarily, but over the time, bacteria and other microbes may get entrapped into the threads of the mask itself and thus acting as a storage chamber of microbes. It is necessary to eliminate them from the mask surface. To do so different floral structured Nano‐ZnO with variable oriented arrangement of petals were fabricated on the surface of the N95 mask and further characterized through instrumentations including XRD, FTIR, UV–vis, fluorescence‐spectroscopy, SEM, DLS. The average crystallite size calculated for synthesized four different ZnO nanoflower were 25.19, 23.46, 27.27, and 31.78 nm (for glycerol, PEG, EDTA, chitosan‐assisted), respectively. The antimicrobial activity was investigated by the standard microbial broth dilution assay and the Kirby–Bauer test, which assured the inhibition of the bacterial growth. The MIC‐MBC value of ZnO nanoflowers for Escherichia coli and Bacillus subtilis were found to be effective at dilution of 250 and 100 µg/mL. Additionally, a modified Kirby–Bauer assay has been designed to investigate the killing efficiency of the bacteria ( E. coli ).