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While the ongoing COVID‐19 pandemic affirms an urgent global need for effective vaccines as second and third infection waves are spreading worldwide and generating new mutant virus strains, it has also revealed the importance of mitigating the transmission of SARS‐CoV‐2 through the introduction of restrictive social practices. Here, it is demonstrated that an architecturally‐ and chemically‐diverse family of nanostructured anionic polymers yield a rapid and continuous disinfecting alternative to inactivate coronaviruses and prevent their transmission from contact with contaminated surfaces. Operating on a dramatic pH‐drop mechanism along the polymer/pathogen interface, polymers of this archetype inactivate the SARS‐CoV‐2 virus, as well as a human coronavirus surrogate (HCoV‐229E), to the minimum detection limit within minutes. Application of these anionic polymers to frequently touched surfaces in medical, educational, and public‐transportation facilities, or personal protection equipment, can provide rapid and repetitive protection without detrimental health or environmental complications. [ABSTRACT FROM AUTHOR]

The prolonged survival of microbes on surfaces in high-traffic/high-contact environments drives the need for a more consistent and passive form of surface sterilization, with the goal of minimizing pathogen transmission. Here, we developed self-disinfecting materials through the covalent attachment of a porphyrin-based photosensitizer (PS) to nanofibrillated cellulose (NFC) and paper (Pap), imparting antimicrobial activity to these renewable scaffolds via photodynamically generated singlet oxygen. The facile covalent attachment of the free-base 5-(4-aminophenyl)-10,15,20-tris-(4-N-methylpyridinium)porphyrin (A3B3+) and metallated [5-(4-aminophenyl)-10,15,20-tris-(4-N-methylpyridinium)porphyrinato]zinc(ii) (Zn-A3B3+) photosensitizers was accomplished by aqueous cyanuric chloride coupling, avoiding the use of organic solvents of previous coupling strategies, while preventing PS leaching that is an issue with non-covalent PS incorportation strategies. Materials characterization and the degree of photosensitizer loading were determined by FTIR, elemental and TGA analyses, and UV-Visible Diffuse Reflectance Spectroscopy (UV-Vis DRS). The antimicrobial potencies of the resultant PS-NFC and PS-Pap materials were evaluated against four strains of bacteria recognized by the World Health Organization as either critical or high priority pathogens: Gram-positive strains methicillin-resistant S. aureus (MRSA; ATCC-44) and vancomycin-resistant E. faecium (VRE; ATCC-2320), and Gram-negative strains multidrug-resistant A. baumannii (MDRAB; ATCC-1605) and NDM-1 positive K. pneumoniae (KP; ATCC-2146). Our results demonstrated broad photodynamic inactivation of all strains studied upon illumination (30 min; 65 ± 5 mW cm−2; 400–700 nm) by a minimum of 99.999%. Antiviral studies against two enveloped viruses, dengue-1 (DENV) and vesicular stomatitis virus (VSV), revealed complete inactivation by both materials. Taken together, the results demonstrate the potential for photoactive NFC as the basis for sustainable broad spectrum anti-infective materials. [ABSTRACT FROM AUTHOR]