Bactericidal and biocatalytic temperature responsive microgel based self-cleaning membranes for water purification

The present study focuses on creating an antimicrobial and biocatalytic smart gating membrane by syn-thesizing unique core-shell microgels. The core-shell microgels are synthesized by grafting short chains of poly(ethylenimine) (PEI) onto a poly((N-isopropyl acrylamide)-co-glycidyl methacrylate)) (P(NIPAm-co-GMA)) core. Subsequently, the produced microgels are utilized as a substrate for synthesizing and sta-bilizing silver nanoparticles (Ag NPs) through an in-situ approach. These Ag NPs immobilized microgels are then suction filtered over a polyethylene terephthalate (PET) track-etched support to create cross-linked composite microgel membranes (CMMs). After structural and permeation characterization of the prepared CMMs, the laccase enzyme is then covalently grafted to the surface of the membrane and tested for its effectiveness in degrading Reactive red-120 dye. The laccase immobilized biocatalytic CMMs show effective degradation of the Reactive red-120 by 71%, 48%, and 34% at pH 3, 4, and 5, respec-tively. Furthermore, the immobilized laccase enzyme showed better activity and stability in terms of thermal, pH, and storage compared to the free laccase, leading to increased reusability. The unique com-bination of Ag NPs and laccase on a thermoresponsive microgel support resulted in a responsive self-cleaning membrane with excellent antimicrobial and dye degradation capabilities for environmentally friendly separation technology.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

The present study focuses on creating an antimicrobial and biocatalytic smart gating membrane by synthesizing unique core-shell microgels. These microgels are used as a substrate for synthesizing and stabilizing silver nanoparticles (Ag NPs), and then filtered to create cross-linked composite microgel membranes (CMMs). The immobilized laccase enzyme on the surface of the membrane shows effective degradation of Reactive red-120 dye, with improved activity and stability compared to free laccase. This responsive self-cleaning membrane has excellent antimicrobial and dye degradation capabilities for environmentally friendly separation technology.