Surface Functionalization of Polyethersulfone Membrane with Quaternary Ammonium Salts for Contact-Active Antibacterial and Anti-Biofouling Properties

Abstract

Biofilm is a significant cause for membrane fouling. Antibacterial-coated surfaces can inhibit biofilm formation by killing bacteria. In this study, polyethersulfone (PES) microfiltration membrane was photografted by four antibiotic quaternary ammonium compounds (QACs) separately, which were synthesized from dimethylaminoethyl methacrylate (DMAEMA) by quaternization with butyl bromide (BB), octyl bromide (OB), dodecyl bromide (DB), or hexadecyl bromide (HB). XPS, ATR-FTIR, and SEM were used to confirm the surfaces’ composition and morphology. After modification, the pores on PES-g-DMAEMA-BB and PES-g-DMAEMA-OB were blocked, while PES-g-DMAEMA-DB and PES-g-DMAEMA-HB were retained. We supposed that DMAEMA-BB and DMAEMA-OB aggregated on the membrane surface due to the activities of intermolecular or intramolecular hydrogen bonds. Bacteria testing found the antibacterial activities of the membranes increased with the length of the substituted alkyl chain. Correspondingly, little bacteria were observed on PES-g-DMAEMA-DB and PES-g-DMAEMA-HB by SEM. The antifouling properties were investigated by filtration of a solution of Escherichia coli. Compared with the initial membrane, PES-g-DMAEMA-DB and PES-g-DMAEMA-HB showed excellent anti-biofouling performance with higher relative flux recovery (RFR) of 88.3% and 92.7%, respectively. Thus, surface functionalization of the PES membrane with QACs can prevent bacteria adhesion and improve the anti-biofouling activity by the contact-active antibacterial property.

Facile Incorporation of Silver Nanoparticles into Quaternized Poly(2-(Dimethylamino)Ethyl Methacrylate) Brushes as Bifunctional Antibacterial Coatings

“…One of the most extensively studied polycationic brush is quaternized poly(2‐(dimethylamino)ethyl methacrylate) (qPDMAEMA) . The factors influencing qPDMAEMA's antibacterial activities include the cationic charge density, the length of alkyl halide used for quaternization, as well as the ampliphilicity of polymer chains . However, the polycationic brushes can only kill the first layer of bacteria.…”

The Key Role of Modifications in Biointerfaces toward Rendering Antibacterial and Antifouling Properties in Polymeric Membranes for Water Remediation: A Critical Assessment

“…[124] In PES based membranes when a polymer poly(2-((2-hydroxy-3-(methacryloyloxy)propyl)dimethylammonio)acetate) was anchored by photopolymerization, the resistance against Pseudomonas fluorescens was enhanced. [128] In a different study by Samantaray et al, when PVDF is blended with styrene maleic anhydride and grafted with QAC, the protein fouling and bactericidal response of the modified membranes were enhanced. In a study by Hu et al when PES membranes were tethered with four different QACs using photoinitiation method, the antibacterial resistance toward E. coli and S. aureus was drastically improved.…”

“…The antibacterial activity of these compounds was studied as early as the 1900s and it was clinically been used by surgeons for sterilization. [7] Foulants adsorbed at the membrane surfaces can be removed by back-flushing and this might be the key reason due to which reports on PVDF [52,85,87,[124][125][126] and PES [127,128] based membranes modified with QACs exhibited good fouling resistance. Being a cationic agent, the mode of action is sequential and similar to that of primary amine derivatives.…”

A novel nanofiltration membrane with simultaneously enhanced antifouling and antibacterial properties

“…Nano-size metal particulates with enhanced surface areas exhibit superb antimicrobial properties. [12][13][14] The most common way to improve the hydrophilicity of a membrane surface to mitigate organics deposition onto the membrane surface is the adhesion of a hydrophilic coating to the upper membrane layer. [15][16][17] Commonly used methods are: a hydrophilic polymer is chemically modied and graed onto the surface of the lm by coating or plasma polymerization, so that the hydrophilicity of the lm surface is greatly improved.…”