title: Polyelectrolyte and silver nanoparticle modification of microfiltration membranes to mitigate organic and bacterial fouling.
abstract: Membrane fouling remains one of the most problematic issues surrounding membrane use in water and wastewater treatment applications. Organic and biological fouling contribute to irreversible fouling and flux decline in these processes. The aim of this study was to reduce both organic and biological fouling by modifying the surface of commercially available poly(ether sulfone) (PES) membranes using the polyelectrolyte multilayer modification method with poly(styrenesulfonate) (PSS), poly(diallyldimethylammonium chloride) (PDADMAC), and silver nanoparticles (nanoAg) integrated onto the surface as stable, thin (15 nm) films. PSS increases the hydrophilicity of the membrane and increases the negative surface charge, while integration of nanoAg into the top PSS layer imparts biocidal characteristics to the modified surface. Fouling was simulated by filtering aqueous solutions of humic acid (5 and 20 mg L(-1)), a suspension of  Escherichia coli  (10(6) colony-forming units (CFU) mL(-1)), and a mixture of both foulants through unmodified and modified PES membranes under batch conditions. Filtration and cleaning studies confirmed that the modification significantly reduced organic and biological fouling.
authors.affiliation: Department of Civil and Environmental Engineering, Howard University, Washington, DC 20059, United States.
authors.forename: Fatou
authors.initials: F
authors.lastname: Diagne
authors.forename: Ramamoorthy
authors.initials: R
authors.lastname: Malaisamy
authors.forename: Vic
authors.initials: V
authors.lastname: Boddie
authors.forename: R David
authors.initials: RD
authors.lastname: Holbrook
authors.forename: Broderick
authors.initials: B
authors.lastname: Eribo
authors.forename: Kimberly L
authors.initials: KL
authors.lastname: Jones
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D057219:Biofouling / Q000517:prevention & control*; D004573:Electrolytes / Q000737:chemistry*; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism; D005374:Filtration / Q000295:instrumentation* / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions / Q000187:drug effects; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D008856:Microscopy, Fluorescence; D009930:Organic Chemicals / Q000737:chemistry; D011095:Polyethylenes / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D004573:Electrolytes; D008567:Membranes, Artificial; D009930:Organic Chemicals; D011095:Polyethylenes; D011137:Polystyrenes; D000644:Quaternary Ammonium Compounds; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; D012834:Silver; C003321:polystyrene sulfonic acid