Polyelectrolyte multilayers as anti-adhesive membrane coatings for virus concentration and recovery

Crossflow membrane filtration is emerging as a concentration method for the recovery and detection of viruses in large volumes of water. To increase virus recovery, an ultrafiltration membrane is usually blocked with a proteinaceous solution or a chemical dispersant. This proof-of-concept study explores a novel approach using controlled and rapid (< 1 h) layer-by-layer adsorption of polyelectrolytes to form an anti-adhesive, sacrificial layer on the membrane surface. Compared to membranes blocked with calf serum (CS), membranes coated with polyelectrolyte multilayer (PEM) films show significantly higher pre-elution recoveries of P22 bacteriophage from both deionized water (80% versus 27% recovery) and from MBR effluent (47% versus 35% recovery) under high crossflow conditions. Calculations of virus-membrane interaction energies confirm that the higher recoveries with PEM-coated membranes are due to their higher charge and hydrophilicity relative to CS-blocked membranes. The high pre-elution recovery from simple water matrices with PEM-coated membranes might eliminate the need for elution and backflushing steps, thus reducing both the time required for pathogen concentration and the volume of the final sample. The proposed methodology can be used to guide the rational design of membrane surfaces with controllable adhesion properties with respect to a broad range of viruses and other pathogens. (C) 2014 Elsevier B.V. All rights reserved.