title: Deposition kinetics of bacteriophage MS2 to natural organic matter: role of divalent cations.
abstract: The role of divalent cations (i.e. Ca(2+) and Mg(2+)) in the deposition kinetics of the bacteriophage MS2 onto flat bare silica surfaces and Suwannee River Natural Organic Matter (SRNOM)-coated silica surfaces was investigated using a Quartz Crystal Microbalance (QCM) coupled with a radial stagnation point flow (RSPF) system. Experimental results demonstrated that attachment efficiencies of MS2 onto the SRNOM surface were seven to seventeen times higher in the presence of Ca(2+) than in the presence of Mg(2+). A similar trend was observed for the adsorption of polyglutamic acid, which is one of the carboxylate-containing amino acid residues found on the surface of MS2 capsids present on SRNOM-coated surfaces. The difference in attachment rates in a solution containing either Ca(2+) or Mg(2+) can be explained by a stronger tendency of Ca(2+) compared to Mg(2+) to form cation bridges by binding to carboxylate groups of both the SRNOM and the MS2 capsids. Moreover, higher attachment efficiencies of MS2 onto the SRNOM-coated silica surfaces compared to those on bare silica surfaces in the presence of either Ca(2+) or Mg(2+) at concentrations higher than 0.3 mM emphasized the important role of SRNOM carboxylate groups. Experimental data also showed reduced attachment efficiency of MS2 to SRNOM-coated surfaces in solution containing 1 mg/L SRNOM.
authors.affiliation: Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, The Center of Advanced Materials for the Purification of Water with Systems, United States. maipham2@uiuc.edu
authors.forename: Mai
authors.initials: M
authors.lastname: Pham
authors.forename: Eric A
authors.initials: EA
authors.lastname: Mintz
authors.forename: Thanh H
authors.initials: TH
authors.lastname: Nguyen
mesh_terms: D000327:Adsorption; D001422:Bacterial Adhesion; D002118:Calcium / Q000737:chemistry / Q000502:physiology*; D007700:Kinetics; D017909:Levivirus / Q000378:metabolism*; D008274:Magnesium / Q000737:chemistry / Q000502:physiology*; D011791:Quartz; D012822:Silicon Dioxide / Q000737:chemistry; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D011791:Quartz; D012822:Silicon Dioxide; D008274:Magnesium; D002118:Calcium