Surfactant-Enhanced Electrospun Nanofiber Filters for Efficient Viral and Bacterial Inactivation

Abstract

Air pollution caused by particulate matter (PM) and bioaerosols, including viruses and bacteria, represents a major global health concern. The development of air filters combining high filtration efficiency with antimicrobial activity is therefore essential. This study investigates electrospun polyacrylonitrile (PAN) nanofibers functionalized with cetylpyridinium chloride (CPC), cetyltrimethylammonium bromide (CTAB), and sodium dodecyl sulfate (SDS), evaluating their PM0.3 filtration performance and antimicrobial activity. PAN nanofibers were produced from 8 wt% PAN solutions containing 1.5%, 2.0%, and 2.5% surfactant. Solution viscosity and electrical conductivity were measured, and the filters were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, contact angle measurements, and x-ray photoelectron spectroscopy (XPS). Antibacterial and antiviral performances were systematically assessed. Nanofiber diameters ranged from 431 to 712 nm, achieving filtration efficiencies of up to 99.92% with pressure drops between 42 and 269 Pa. Surfactant incorporation significantly enhanced antimicrobial performance. PAN nanofibers containing 2.5% CPC achieved bacterial reductions of 99.58% for Staphylococcus aureus and 99.65% for Escherichia coli, while filters containing 1.5% surfactant achieved approximately 4-log (99.99%) inactivation of SARS-CoV-2. These results demonstrate that surfactant-functionalized PAN nanofibers are promising candidates for advanced air filtration applications.