The effect of re-generable silver nanoparticles/multi-walled carbon nanotubes coating on the antibacterial performance of hollow fiber membrane

We report a simple and efficient technique to deposit a re-generable coating of silver nanoparticles/multi-walled carbon nanotubes (Ag/MWNTs) on the surface of hollow fiber membrane by filtration. The resultant disinfection layer consists of porous and entangled network of Ag/MWNTs which is sufficiently stable for normal filtration operation. This physical attachment method resulted in insignificant water flux drop since chemical treatment or photon/plasma-assisted sputtering of the membrane was not involved. The composite membrane significantly reduces the formation of biofilm due to the presence of silver nanoparticles on the membrane surface and the leached silver ions. Upon depletion of the silver content due to silver leaching, the coating can be easily detached from the membrane surface and replenished with silver nanoparticles for recycle, while retaining good antimicrobial performances for prolonged use. The technique used in this study can be extended to other types of antimicrobial agents, the support materials and membranes.