Surface hydrophilization of microporous polypropylene membrane by grafting zwitterionic polymer for anti-biofouling

Abstract The anti-biofouling properties, i.e. the resistance to protein adsorption and the inhibition of bacterial adhesion (biofilm formation) are of vital importance to separation membranes. Surface hydrophilization is thought to be the most common approach to improve these performances for hydrophobic polymer membranes, such as microporous polypropylene membrane (MPPM). In this work, MPPM was highly hydrophilized by the UV-induced grafting of polysulfobetaine methacrylate (polySBMA), an outstanding representative of zwitterionic anti-/non-fouling polymers. A sequential grafting strategy was improved by combining the conventional benzophenone entrapment and covalent immobilization methods. FT-IR/ATR, XPS and FESEM were used to characterize the detailed surface structures of MPPM. The hydrophilization effect was evaluated by water contact angle (WCA) and pure water flux measurements. Besides, both protein filtration and initial adhesion of bacteria were performed to investigate the anti-biofouling properties of the modified MPPM. The surface hydrophobicity of the bacteria was also measured and correlated with the adhesion results. It is found that the improved strategy allows the grafting to take place on the external surface and the grafting density to be well controlled by modulating the SBMA concentration. The surface hydrophilicity of MPPM is significantly enhanced, characterized by a decrease of WCA from 145 to ∼15° and an increase of flux by 4 times. These hydrophilized MPPM has strong resistance to protein fouling, having a flux recovery ratio higher than 95% under optimized conditions. The initial adhesion of bacteria on the MPPM can be completely suppressed when the grafting density reaches 560 μg/cm 2 , regardless of the bacterial surface hydrophobicity.

[1]  Shuichi Takayama,et al.  Zwitterionic SAMs that Resist Nonspecific Adsorption of Protein from Aqueous Buffer. , 2001, Langmuir : the ACS journal of surfaces and colloids.

[2]  Lewis,et al.  Phosphorylcholine-based polymers and their use in the prevention of biofouling. , 2000, Colloids and surfaces. B, Biointerfaces.

[3]  J. Kang,et al.  Colloidal Adsorption of Bovine Serum Albumin on Porous Polypropylene-g-Poly(2-hydroxyethyl methacrylate) Membrane , 2001 .

[4]  M. Ulbricht,et al.  Polypropylene-based membrane adsorbers via photo-initiated graft copolymerization: Optimizing separation performance by preparation conditions , 2008 .

[5]  Shaoyi Jiang,et al.  Highly protein-resistant coatings from well-defined diblock copolymers containing sulfobetaines. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[6]  Zhongyi Jiang,et al.  Highly efficient antifouling ultrafiltration membranes incorporating zwitterionic poly([3-(methacryloylamino)propyl]-dimethyl(3-sulfopropyl) ammonium hydroxide) , 2009 .

[7]  Shaoyi Jiang,et al.  Strong resistance of phosphorylcholine self-assembled monolayers to protein adsorption: insights into nonfouling properties of zwitterionic materials. , 2005, Journal of the American Chemical Society.

[8]  Robert H. Davis,et al.  A Novel Sequential Photoinduced Living Graft Polymerization , 2000 .

[9]  Y. An,et al.  Concise review of mechanisms of bacterial adhesion to biomaterial surfaces. , 1998, Journal of biomedical materials research.

[10]  Zhi-Kang Xu,et al.  Surface modification of polypropylene microporous membrane to improve its antifouling property in MBR: CO2 plasma treatment , 2005 .

[11]  Zhongyi Jiang,et al.  Antifouling ultrafiltration membrane composed of polyethersulfone and sulfobetaine copolymer , 2006 .

[12]  H. C. van der Mei,et al.  Microbial adhesion to poly(ethylene oxide) brushes: influence of polymer chain length and temperature. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[13]  Wantai Yang,et al.  Radical living graft polymerization on the surface of polymeric materials , 1996 .

[14]  H. Busscher,et al.  Implications of microbial adhesion to hydrocarbons for evaluating cell surface hydrophobicity 1. Zeta potentials of hydrocarbon droplets , 1995 .

[15]  Yiming Cao,et al.  Enhancing antifouling property of polysulfone ultrafiltration membrane by grafting zwitterionic copolymer via UV-initiated polymerization , 2009 .

[16]  E. Olivetti,et al.  Fouling resistant, high flux nanofiltration membranes from polyacrylonitrile-graft-poly(ethylene oxide) , 2009 .

[17]  Shaoyi Jiang,et al.  Inhibition of bacterial adhesion and biofilm formation on zwitterionic surfaces. , 2007, Biomaterials.

[18]  Wilhelm T S Huck,et al.  UCST wetting transitions of polyzwitterionic brushes driven by self-association. , 2006, Angewandte Chemie.

[19]  Paitoon Tontiwachwuthikul,et al.  Using polypropylene and polytetrafluoroethylene membranes in a membrane contactor for CO2 absorption , 2006 .

[20]  Koon Gee Neoh,et al.  Surface Functionalization Technique for Conferring Antibacterial Properties to Polymeric and Cellulosic Surfaces , 2003 .

[21]  G. Belfort,et al.  Surface modification of ultrafiltration membranes by low temperature plasma II. Graft polymerization onto polyacrylonitrile and polysulfone , 1996 .

[22]  M. Ulbricht,et al.  Photo-irradiation for preparation, modification and stimulation of polymeric membranes , 2009 .

[23]  Matthias Wessling,et al.  Medical applications of membranes: Drug delivery, artificial organs and tissue engineering , 2008 .

[24]  W. Huck,et al.  Thickness-Dependent Properties of Polyzwitterionic Brushes , 2008 .

[25]  Heru Susanto,et al.  Photografted thin polymer hydrogel layers on PES ultrafiltration membranes: characterization, stability, and influence on separation performance. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[26]  Zhi‐Kang Xu,et al.  Surface hydrophilization of microporous polypropylene membrane by the interfacial crosslinking of polyethylenimine , 2009 .

[27]  Shaoyi Jiang,et al.  Superlow fouling sulfobetaine and carboxybetaine polymers on glass slides. , 2006, Langmuir : the ACS journal of surfaces and colloids.

[28]  Robert H. Davis,et al.  Principal factors affecting sequential photoinduced graft polymerization , 2001 .

[29]  A. Drews,et al.  Recent advances in membrane bioreactors (MBRs): membrane fouling and membrane material. , 2009, Water research.

[30]  G. Whitesides,et al.  A Survey of Structure−Property Relationships of Surfaces that Resist the Adsorption of Protein , 2001 .

[31]  M. Ulbricht,et al.  Porous Polypropylene Membranes with Different Carboxyl Polymer Brush Layers for Reversible Protein Binding via Surface-Initiated Graft Copolymerization , 2005 .

[32]  Zhi‐Kang Xu,et al.  Surface modification of polypropylene microporous membranes with a novel glycopolymer , 2005 .

[33]  Kamalesh K. Sirkar,et al.  Interfacially polymerized hydrophilic microporous thin film composite membranes on porous polypropylene hollow fibers and flat films , 2006 .

[34]  Eugene Rosenberg,et al.  Adherence of bacteria to hydrocarbons: A simple method for measuring cell‐surface hydrophobicity , 1980 .

[35]  Fang Yao,et al.  Antibacterial effect of surface-functionalized polypropylene hollow fiber membrane from surface-initiated atom transfer radical polymerization , 2008 .

[36]  Akon Higuchi,et al.  Sulfobetaine-grafted poly(vinylidene fluoride) ultrafiltration membranes exhibit excellent antifouling property , 2009 .

[37]  J. Costerton,et al.  Bacterial biofilms: a common cause of persistent infections. , 1999, Science.

[38]  Hans-Curt Flemming,et al.  Biofouling—the Achilles heel of membrane processes☆ , 1997 .

[39]  Pierre Le-Clech,et al.  Fouling in membrane bioreactors used in wastewater treatment , 2006 .

[40]  S. Armes,et al.  Synthesis and Properties of Low-Polydispersity Poly(sulfopropylbetaine)s and Their Block Copolymers , 1999 .

[41]  Kazuhiko Ishihara,et al.  Phosphorylcholine-containing polymers for biomedical applications , 2005, Analytical and bioanalytical chemistry.

[42]  Zhi-Kang Xu,et al.  Surface engineering of macroporous polypropylene membranes , 2009 .

[43]  C. McCormick,et al.  Synthesis and solution properties of zwitterionic polymers. , 2002, Chemical reviews.

[44]  E. R. Fisher,et al.  Membrane Surface Modification by Plasma-Induced Polymerization of Acrylamide for Improved Surface Properties and Reduced Protein Fouling , 2003 .

[45]  A. Zydney,et al.  Ultrafiltration of PEGylated proteins: Fouling and concentration polarization effects , 2008 .

[46]  Shaoyi Jiang,et al.  Surface grafted sulfobetaine polymers via atom transfer radical polymerization as superlow fouling coatings. , 2006, The journal of physical chemistry. B.