文章基本信息

标题：Pyrite-induced hydroxyl radical formation and its effect on nucleic acids
本地全文：下载
作者：Corey A Cohn ; Steffen Mueller ; Eckard Wimmer 等
期刊名称：Geochemical Transactions
电子版ISSN：1467-4866
出版年度：2006
卷号：7
期号：1
页码：1-11
DOI：10.1186/1467-4866-7-3
出版社：BioMed Central
摘要：Pyrite, the most abundant metal sulphide on Earth, is known to spontaneously form hydrogen peroxide when exposed to water. In this study the hypothesis that pyrite-induced hydrogen peroxide is transformed to hydroxyl radicals is tested. Using a combination of electron spin resonance (ESR) spin-trapping techniques and scavenging reactions involving nucleic acids, the formation of hydroxyl radicals in pyrite/aqueous suspensions is demonstrated. The addition of EDTA to pyrite slurries inhibits the hydrogen peroxide-to-hydroxyl radical conversion, but does not inhibit the formation of hydrogen peroxide. Given the stability of EDTA chelation with both ferrous and ferric iron, this suggests that the addition of the EDTA prevents the transformation by chelation of dissolved iron species. While the exact mechanism or mechanisms of the hydrogen peroxide-to-hydroxyl radical conversion cannot be resolved on the basis of the experiments reported in this study, it is clear that the pyrite surface promotes the reaction. The formation of hydroxyl radicals is significant because they react nearly instantaneously with most organic molecules. This suggests that the presence of pyrite in natural, engineered, or physiological aqueous systems may induce the transformation of a wide range of organic molecules. This finding has implications for the role pyrite may play in aquatic environments and raises the question whether inhalation of pyrite dust contributes to the development of lung diseases.
关键词：Electron Spin Resonance;Pyrite;Ferrous Iron;Fenton Reaction;Ferrous Ammonium Sulfate