title: Bactericidal effect of zero-valent iron nanoparticles on Escherichia coli.
abstract: Zero-valent iron nanoparticles (nano-Fe0) in aqueous solution rapidly inactivated Escherichia coli. A strong bactericidal effect of nano-Fe0 was found under deaerated conditions, with a linear correlation between log inactivation and nano-Fe0 dose (0.82 log inactivation/mg/L nano-Fe0 x h). The inactivation of E. coli under air saturation required much higher nano-Fe0 doses due to the corrosion and surface oxidation of nano-Fe0 by dissolved oxygen. Significant physical disruption of the cell membranes was observed in E. coli exposed to nano-Fe0, which may have caused the inactivation or enhanced the biocidal effects of dissolved iron. The reaction of Fe(II) with intracellular oxygen or hydrogen peroxide also may have induced oxidative stress by producing reactive oxygen species. The bactericidal effect of nano-Fe0 was a unique property of nano-Fe0, which was not observed in other types of iron-based compounds.
authors.affiliation: Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, USA.
authors.forename: Changha
authors.initials: C
authors.lastname: Lee
authors.forename: Jee Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Won Il
authors.initials: WI
authors.lastname: Lee
authors.forename: Kara L
authors.initials: KL
authors.lastname: Nelson
authors.forename: Jeyong
authors.initials: J
authors.lastname: Yoon
authors.forename: David L
authors.initials: DL
authors.lastname: Sedlak
mesh_terms: D002462:Cell Membrane / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects* / Q000648:ultrastructure; D007501:Iron / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000633:toxicity*; D010084:Oxidation-Reduction
chemical_list: D007501:Iron