Antibacterial and antiviral activity of a highly efficient electrospun r-PET nanofiber

Since the COVID-19 pandemic, the emergence of clean air has increased interest in developing antimicrobial air filters, targeting sterilization and public health concerns. Nanofibers are a promising approach due to their high efficiency in air filtration, while nanoparticles adhered to the fibre surfaces can improve safety due to the biocidal effects. In this study, CuNPs were developed using a green method in a redox reaction, with CuSO₄ ∙ 5H₂O, ascorbic acid, and polyvinyl pyrrolidone (PVP). Membranes were prepared using recycled polyethylene terephthalate (PET) bottles (r-PET) by electrospinning and the biocidal effect was given by applying CuNP in surface membranes by spraying. The collection time and rotation speed varied between 30 to 90 min and between 176 and 355 rpm, respectively. The permeability (k₁) and the particle collection efficiency $\eta$ (%) of the membranes were measured for each combination. Results showed the Darcy's permeability in order of 10⁻¹²  m², and overall efficiency up to 99.81% for particle diameters below 290 nm, with enhanced particle collection for nanoparticles (<100 nm). The membranes coated with copper nanoparticles (CuNP) showed a reduction of 99.99% for E. coli and S. aureus as gram-negative and gram-positive bacteria, respectively, even in low concentrations. Membranes coated with CuNP were effective against Yellow Fever and SARS-CoV-2 viruses, with viral reduction of 99.13% and 93.00%, respectively. The electrospun membranes developed in this study are versatile and can be utilized in various applications such as indoor air filters, portable air filters, wound dressings, medical equipment, and masks. Their usage enhances safety during material handling and usage.