Abstract:
Water scarcity and quality challenges facing the world can be alleviated by Point-of-Use filtration devices (POU). ,e use offiltration membranes in POU devices has been limited largely because of membrane fouling, which occurs when suspended solids,microbes, and organic materials are deposited on the surface of filtration membranes significantly decreasing the membranelifespan, thereby increasing operation costs. ,ere is need therefore to develop filtration membranes that are devoid of thesechallenges. In this work, nanotechnology was used to fabricate nanostructured polyamic acid (nPAA) membranes, which can beused for microbial decontamination of water. ,e PAA was used as support and reducing agent to introduce silver nanoparticles(AgNPs) and gold nanoparticles (AuNPs) with antimicrobial properties. ,e nPAA membranes were fabricated via thermal andwet phase inversion technique and then tested againstEscherichia coliandStaphylococcus aureusfollowing standard tests. ,eresulting nanoparticles exhibited excellent dispersibility and stability as indicated by the color change of the solution and in-crements of optical density at 415 nm for AgNPs and 520 nm for AuNPs. ,e wet phase inversion process used produced highlyporous, strong, and flexible nPAA membranes, which showed well-dispersed spherical AuNPs and AgNPs whose rough averagesize was found to be 35 nm and 25 nm, respectively. ,e AgNPs demonstrated inhibition for both gram positiveE. coliand gramnegativeS. aureus, with a better inhibitory activity againstS. aureus. A synergistic enhancement of AgNPs antimicrobial activityupon AuNPs addition was demonstrated. ,e nPAA membranes can thus be used to remove microbials from water and can hencebe used in water purification.
