Fast-acting and highly rechargeable antibacterial composite nanofibrous membrane for protective applications

Abstract Bacterial infection has been globally recognized as one of the most prominent public health safety concerns, and the untreated surfaces are highly susceptible to the bacterial deposition and breeding without protective covers, thus the fabrication of potent membranes for shielding and combating bacteria is of vital importance. In this study, a powerful nanofibrous membrane on inactivating bacteria was fabricated based on a N-halamine polymeric system, which included a hydrophobic thermoplastic polyurethane (TPU) and a hydrophilic modified polyacrylic acid (PAA), and the fabricated membrane was called as TPM. According to the systematic investigations, TPM exhibited excellent antibacterial and antivirus activity, the minimum inhibitory concentration to E. coli and S. aureus was 1.4 mg/mL. Upon contact, above 95% of both bacteria (≈106 CFU/mL) could be killed within 5 min, and the antiviral activity rate of TPM reached to above 99.92%. TPM also possessed a rapid chlorine loading capacity, which could completely load the active chlorine within 1 h, and the loading content of active chlorine rarely reduced even after five chlorination-quenching cycles, indicating excellent regenerative chlorination capacity. Additionally, the antibacterial mechanism in terms of macromolecular release, morphological damage and the reduction of respiratory chain dehydrogenase activity were studied. The resulting TPM with superior antibacterial performance can serve as a scalable biocidal layer for protective applications, and the facile synthesis of the TPM may also provide a strategy to develop protective materials in a sustainable, rechargeable, and structurally adaptive form.