Lee Changha, Kim Jee Yeon, Lee Won Il, Nelson Kara L, Yoon Jeyong, Sedlak David L
Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, USA.
Environ Sci Technol. 2008 Jul 1;42(13):4927-33. doi: 10.1021/es800408u.
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.
水溶液中的零价铁纳米颗粒（nano-Fe0）能迅速使大肠杆菌失活。在脱气条件下发现nano-Fe0具有很强的杀菌效果，对数失活与nano-Fe0剂量之间呈线性相关（0.82对数失活/mg/L nano-Fe0×h）。由于溶解氧对nano-Fe0的腐蚀和表面氧化作用，在空气饱和条件下使大肠杆菌失活需要更高剂量的nano-Fe0。在暴露于nano-Fe0的大肠杆菌中观察到细胞膜出现明显的物理破坏，这可能导致了失活或增强了溶解铁的杀菌作用。Fe(II)与细胞内氧气或过氧化氢的反应也可能通过产生活性氧诱导氧化应激。nano-Fe0的杀菌作用是nano-Fe0的独特性质，在其他类型的铁基化合物中未观察到。
