Enhancing polysulfone membrane performance: The role of ZIF-8 nanoparticles in biofilm control and antimicrobial activity against <i>Staphylococcus aureus</i> and <i>Pseudomonas aeruginosa</i>

To control biofilm in membranes through the performance enhancement of polysulfone membranes, ZIF-8 nanoparticles (NPs) were mixed into membranes.This research investigated the antimicrobial activity and biofilm dispersal capabilities of ZIF-8 nanoparticle membranes in relation to Staphylococcus aureus and Pseudomonas aeruginosa.This study used room temperature solution reaction method for synthesizing ZIF-8 NPs and characterized the materials with SEM, EDX, ZETA potential, and FTIR.Biofilm inhibition tests were conducted with results indicating that a concentration of 2.5 mg/mL ZIF-8 NPs resulted in a 99.3% inhibition rate in Staphylococcus aureus biofilm formation.P. aeruginosa biofilm formation was reduced to 96% with a higher concentration of ZIF-8 NPs at 5 mg/mL.ZIF-8 membranes (0 wt%, 0.025 wt%, 0.05 wt%, and 0.075 wt%) were fluorescently stained to visualize biofilms.The surface coverage of biofilm was (83.74%, 34.267%, 10.24%, and 43.712%) respectively, which indicated that the optimal loading of ZIF-8 NPs was (0.05 wt%).It not only improved biofilm inhibition, but also maintained the structural integrity of the membranes in this loading, whereas higher concentrations resulted in less biofilm reduction due to nanoparticle aggregation.ZIF-8 NPs integration with polysulfone increased porosity and hydrophilicity of the membrane, which in turn will reduce the bacteria's attachment to the membrane surface.There is evidence supporting the claims that ZIF-8 NPs are effective antimicrobial agents and also serve as membrane additives to tackle biofilm for water filtration and other biomedical applications.