期刊
ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS
卷 4, 期 2, 页码 59-65出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.estlett.6b00460
关键词
-
资金
- Office of Biological and Environmental Research (BER), Office of Science, U.S. Department of Energy (DOE), Mercury Science Focus Area at Oak Ridge National Laboratory (ORNL)
- DOE [DE-AC05-00OR22725]
- BER at Pacific Northwest National Laboratory
The chemical speciation and bioavailability of mercury (Hg) is markedly influenced by its complexation with naturally dissolved organic matter (DOM) in aquatic environments. To date, however, analytical methodologies capable of identifying such complexes are scarce. Here, we utilize ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) coupled with electrospray ionization to identify individual Hg-DOM complexes. The measurements were performed by direct infusion of DOM in a 1:1 methanol:water solution at a Hg to dissolved organic carbon (DOC) molar ratio of 3 x 10(-4). Heteroatomic molecules, especially those containing multiple S and N atoms, were found to be among the most important in forming strong complexes with Hg. Major Hg-DOM complexes of C10H21N2S4Hg+ and C8H17N2S4Hg+ were identified based on both the exact molecular mass and patterns of Hg stable isotope distributions detected by FTICR-MS. Density functional theory was used to predict the solution-phase structures of candidate molecules. These findings represent the first step to unambiguously identify specific DOM molecules in Hg binding, although future studies are warranted to further optimize and validate the methodology so as to explore detailed molecular compositions and structures of Hg-DOM complexes that affect biological uptake and transformation of Hg in the environment.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据