title: Inactivation and surface interactions of MS-2 bacteriophage in a TiO2 photoelectrocatalytic reactor.
abstract: Inactivation of MS-2 bacteriophage in a TiO(2) photoelectrocatalytic system was evaluated, wherein TiO(2) particles were coated onto an indium tin oxide (ITO) electrode and an electrical potential was applied under black light blue (BLB) irradiation. MS-2 phage inactivation was greatly enhanced by anodic potential, whereas cathodic potential completely inhibited inactivation. Experiments performed with radical scavengers showed that inactivation was primarily caused by hydroxyl radicals, both in the bulk phase and on the TiO(2) surface. Application of positive potential to the electrode was found to result in two distinct beneficial effects: (i) electrostatic attraction between the negatively charged viral capsid and catalyst surface, causing improved usage of surface-bound hydroxyl radical, in comparison to conventional TiO(2) photocatalytic disinfection; and (ii) higher reactive oxygen species production. Results also suggest that inactivation of various microorganisms including Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Bacillus subtilis spores and Cryptosporidium parvum oocyst was enhanced via positive potential induction to TiO(2).
authors.affiliation: School of Civil and Environmental Engineering, Georgia Institute of Technology, 200 Bobby Dodd Way, Atlanta, GA 30332-0373, USA.
authors.forename: Min
authors.initials: M
authors.lastname: Cho
authors.forename: Ezra L
authors.initials: EL
authors.lastname: Cates
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000302:isolation & purification / Q000528:radiation effects; D019149:Bioreactors / Q000382:microbiology / Q000469:parasitology / Q000821:virology*; D002384:Catalysis / Q000528:radiation effects; D016785:Cryptosporidium parvum / Q000302:isolation & purification / Q000528:radiation effects; D004203:Disinfection / Q000295:instrumentation / Q000379:methods*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D004926:Escherichia coli / Q000302:isolation & purification / Q000528:radiation effects; D007711:Klebsiella pneumoniae / Q000302:isolation & purification / Q000528:radiation effects; D017909:Levivirus / Q000302:isolation & purification* / Q000528:radiation effects; D055668:Photochemical Processes; D017382:Reactive Oxygen Species / Q000737:chemistry; D015203:Reproducibility of Results; D013211:Staphylococcus aureus / Q000302:isolation & purification / Q000528:radiation effects; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D038301:Virus Inactivation / Q000528:radiation effects; D014871:Water Microbiology
chemical_list: D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium