The World Health Organization’s guidelines emphasize that all patient-derived substances are potential infection sources, yet airborne droplets and close contact present additional risks. Masks remain a critical barrier, but improper use—such as lowering them to expose the nose—compromises their protective role. The COVID-19 pandemic underscored the importance of personal protective equipment, with masks central to limiting viral spread. However, single-use surgical masks, while effective, contribute millions of tons of plastic waste annually, intensifying environmental pollution in both terrestrial and marine ecosystems.
Biodegradable biomask filters made from polysaccharides such as coffee, hemp, bamboo, and sugar fibers offer an eco-friendly alternative, but these must also be antimicrobial. Studies have shown that bacteria can proliferate on masks during use, with inner layers often more contaminated than outer ones. This contamination risk increases when masks are removed and reapplied, creating conditions favorable for bacterial growth.
Traditional masks—cotton gauze or melt-blown nonwoven fabrics—focus on blocking droplets. Since the 1960s, surgical masks have relied on melt-blown polypropylene, but nanotechnology now enhances their performance. Nanofibers, with their high surface area and tunable properties, improve filtration efficiency, breathability, and comfort. In biomedical applications, nanoparticles (NPs) such as silver (AgNPs) and titanium dioxide have demonstrated antimicrobial activity, damaging microbial cell membranes without penetrating cells.
Inorganic NPs like graphene have emerged as multifunctional materials for mask fabrication. Graphene cotton fabrics exhibit antibacterial properties and self-sterilize under sunlight, eliminating the need for ovens or chemical disinfectants. Graphene nanosheet-embedded carbon (GNEC) films provide hydrophobic surfaces, achieve 100% photosterilization efficiency under solar illumination, and can be recycled for applications such as water desalination. Superhydrophobicity can be achieved by ultrathin graphene coatings, and antimicrobial effects can be enhanced by adding AgNPs or copper oxide NPs.
Triboelectric (TE) face masks integrate nanogenerators to improve particle capture and deactivate microbes via an electrocution layer. Low-cost TE designs using graphene oxide composites achieve filtration efficiencies above 95% for particles around 300 nm, outperforming conventional N95 masks in electrostatic charge retention.
Silver nanoparticles interact with thiol groups in bacterial proteins, leading to high bacterial growth reduction—up to 99.94% at 20 ppm concentration in cotton/AgNP composites. Copper nanoparticles also exhibit strong bactericidal and bacteriostatic effects against both multidrug-resistant and non-resistant strains, while titanium dioxide generates reactive hydroxyl radicals for microbial inactivation.
Organic NP approaches leverage electrospinning to produce nanofiber membranes from polymers such as polypropylene, polyurethane, and polyacrylonitrile. These membranes filter particulate matter down to 0.31 μm, with reduced thickness enhancing airflow and comfort. Electrospun fibers under 100 nm in diameter can be disinfected and reused without loss of efficiency, offering a scalable, low-cost manufacturing route. Composite nanofibers combining multiple nanomaterials can prevent pathogen accumulation and add functionalities such as electrical conductivity or enhanced mechanical strength.
Graphene oxide (GO) coatings increase mask hydrophobicity and ultraviolet resistance, while reduced graphene oxide (rGO) enhances mechanical stress to physically damage bacterial membranes. GO’s functional groups chemically interact with microbial membranes, disrupting cell integrity. These materials also improve structural integrity and longevity, addressing limitations of traditional masks, which often lose efficiency after decontamination treatments.
Conventional reuse methods—UV exposure, chemical treatments, or steam—either degrade mask structure or reduce filtration efficiency. Nanofabrication offers solutions: antimicrobial surfaces, biodegradable substrates, improved comfort, and extended storage life. Technologies under investigation include copper dioxide, nanodiamonds, biocellulose, laser-induced graphene, and biofunctional coatings such as benzalkonium chloride.
Studies indicate that nanofabricated masks can block ultrafine viruses around 50 nm in size while remaining reusable, lightweight, and environmentally friendly. By integrating materials science advances with practical design considerations, these masks address both public health needs and environmental concerns, positioning nanotechnology as a transformative force in protective equipment engineering.