Polydopamine Nanoconjugate-Coated Masks: An Efficient Barrier Against Airborne Pathogens

Current global burden of respiratory tract infections (RTIs) has thrown new challenges for researchers to design and develop efficient and multifaceted face masks. Airborne pathogens are highly transmissible through droplet nuclei/aerosol (<5 mu m) which can be significantly reduced by wearing masks. Currently available disposable surgical masks have disparate limitations in terms of surface wettability, microbial penetration, dermal infections due to anaerobic reactions beneath the surface, discomfort, and eruption of chronic obstructive pulmonary diseases (COPD). These mask surfaces get contaminated with airborne pathogens along with commensal bacterial strains. Generation of high temperature and humidity during repetitive breathing allow bacteria to penetrate from the masks to respiratory tract causing serious complications. Till date, functionalized face masks with different microbicidal agents including nanomaterials experience restricted leaching of antimicrobial agents, cytotoxic effects, short-lived microbicidal effects, inflammatory responses, negative impact on ecosystem, etc. To address these limitations, here, we have attempted fabrication of mussel mimetic biopolymer (PDA) and its aminoglycoside-nanoconjugate-coated face masks. Formation of a uniform layer on the surface not only acted as a potential barrier for infectious pathogens but also inhibited their entry, deactivated the adhered bacteria, imparted non-immunogenic response with no harmful effects on the wearer's skin owing to the biocompatible nature and pH compatibility of PDA and their conjugates. Amongst all, PDA-kanamycin (PDA-K)-coated masks exhibited excellent microbicidal activity with the least bacterial infiltration efficiency.