Enhancing Polyacrylonitrile Nanofibers Antiviral Activity Using Greenly Synthesized Silver Nanoparticles

Developing efficient antiviral protectives is a new approach against respiratory emerging viruses. This study aims to synthesize silver nanoparticles (Ag NPs) via a green technique using crocin to provide a virucidal effect and to enhance the protection of polyacrylonitrile (PAN) nanofibrous face masks or respirators against viruses. The influence of formulation and process variables on the particle size (PS) of Ag NPs was studied using d-optimal response surface design. The selected NPs were loaded into PAN nanofibers (NFs). MTT colorimetric assay was performed to determine the safety of the prepared NPs and NFs on Vero cells. Further, an immunofluorescent assay was performed to determine the composite's ability to inhibit the ACE2-SARS-CoV-2 spike protein interaction and prevent viral infection. The selected NPs possessed a small PS of 23.21 ± 0.86 nm, a PDI of 0.23 ± 0.019, and a ZP of -21.8 ± 1.82 mV. The optimum NF composite was fabricated with a PAN concentration of 8% w/v loaded with 0.25% w/w Ag NPs, with a feeding rate of 0.7 mL/h and an applied voltage of 23.5 kV. The resultant NFs displayed an acceptable morphology and a mean diameter of 378.88 ± 91.12 nm. In vitro cytotoxicity studies on Vero cells revealed the biocompatibility of crocin and Ag NPs. Moreover, Ag-PAN NFs were proven biologically safe. The immunofluorescent assay showed that Ag-PAN NFs demonstrated the least IC50 value of 10.99 µg/mL, indicating their potent effect on inhibiting SARS-CoV-2 infection. Ag-PAN NFs are a promising safe antiviral composite that has the potential to be used in face masks.