title: Short-term adhesion and long-term biofouling testing of polydopamine and poly(ethylene glycol) surface modifications of membranes and feed spacers for biofouling control.
abstract: Ultrafiltration, nanofiltration membranes and feed spacers were hydrophilized with polydopamine and polydopamine-g-poly(ethylene glycol) surface coatings. The fouling propensity of modified and unmodified membranes was evaluated by short-term batch protein and bacterial adhesion tests. The fouling propensity of modified and unmodified membranes and spacers was evaluated by continuous biofouling experiments in a membrane fouling simulator. The goals of the study were: 1) to determine the effectiveness of polydopamine and polydopamine-g-poly(ethylene glycol) membrane coatings for biofouling control and 2) to compare techniques commonly used in assessment of membrane biofouling propensity with biofouling experiments under practical conditions. Short-term adhesion tests were carried out under static, no-flow conditions for 1 h using bovine serum albumin, a common model globular protein, and Pseudomonas aeruginosa, a common model Gram-negative bacterium. Biofouling tests were performed in a membrane fouling simulator (MFS) for several days under flow conditions similar to those encountered in industrial modules with the autochthonous drinking water population and acetate dosage as organic substrate. Polydopamine- and polydopamine-g-poly(ethylene glycol)-modified membranes showed significantly reduced adhesion of bovine serum albumin and P. aeruginosa in the short-term adhesion tests, but no reduction of biofouling was observed during longer biofouling experiments with modified membranes and spacers. These results demonstrate that short-term batch adhesion experiments using model proteins or bacteria under static conditions are not indicative of biofouling, while continuous biofouling experiments showed that membrane surface modification by polydopamine and polydopamine-g-poly(ethylene glycol) is not effective for biofouling control.
authors.affiliation: Department of Chemical Engineering, The University of Texas at Austin, Center for Energy and Environmental Resources, 10100 Burnet Road, Austin, TX 78758, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Miller
authors.forename: Paula A
authors.initials: PA
authors.lastname: Araújo
authors.forename: Patricia B
authors.initials: PB
authors.lastname: Correia
authors.forename: Matthew M
authors.initials: MM
authors.lastname: Ramsey
authors.forename: Joop C
authors.initials: JC
authors.lastname: Kruithof
authors.forename: Mark C M
authors.initials: MC
authors.lastname: van Loosdrecht
authors.forename: Benny D
authors.initials: BD
authors.lastname: Freeman
authors.forename: Donald R
authors.initials: DR
authors.lastname: Paul
authors.forename: Marvin
authors.initials: M
authors.lastname: Whiteley
authors.forename: Johannes S
authors.initials: JS
authors.lastname: Vrouwenvelder
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D057219:Biofouling; D002417:Cattle; D007211:Indoles / Q000032:analysis* / Q000737:chemistry; D008567:Membranes, Artificial; D011092:Polyethylene Glycols / Q000032:analysis* / Q000737:chemistry; D011108:Polymers / Q000032:analysis* / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000502:physiology; D012709:Serum Albumin / Q000737:chemistry; D013499:Surface Properties
chemical_list: D007211:Indoles; D008567:Membranes, Artificial; D011108:Polymers; D012709:Serum Albumin; C568283:polydopamine; D011092:Polyethylene Glycols