Eco-friendly multi-layered nanoswabs for sensitive removal of antibiotic-resistant bacteria from drinking water sources and their molecular biology studies

Abstract

Recent developments using sustainable nanotechnology have provided effective disinfection methods for wastewater treatment to kill pathogens. However, several issues related to regrowth of pathogens in treated water, generation of harmful by-products, and energy and time consumption in refiltration are unsolved. Additionally, antimicrobial resistance has become a major health concern. In response, we have developed, for the first time, a rapid, effective, and safer water disinfection system consisting of multi-layered cuboid ferric (anhydrous)-triptycene polymer nanoswabs (FATCNS) to kill emerging antibiotic-metal-resistant bacteria and downregulate the antibiotic-resistant genes (ARGs) and disease-causing genes (DCGs) present in four types of water ecosystems. FATCNS strongly inhibit the activity of the enzyme β-galactosidase (GAL) in a geometry-attachment fashion to kill the possibly mutagenic and antibiotic-resistant S. aureus. Further, it shows bactericidal activities against E. coli and antibiotic-metal-resistant bacteria wtKARBJ1 present in different water samples. The seamless hollow nanostructure, which is inherent to multi-layered nanoswabs (NSs), enhances water throughput ability, selectivity to biomolecules, non-tedious filtration, and reusability compared to other existing nanoadsorbents (NAs). The nanoswabs, even in the presence of high pH, salinity and ions, can disinfect water under 1 min and show 85% enhanced antibacterial activity to inhibit 5 × 10⁸ CFU ml⁻¹ bacteria compared to solid Fe₃O₄ nanoparticles (NPs). Such distinctive multi-functional properties of the nanoswabs are attributed to their multi-layer structure, cuboid shape, nano-size, uniform dispersibility in water, and numerous adsorption sites leading to bacterium cell death and effective water disinfection.