Baalousha M, Kammer F V D, Motelica-Heino M, Baborowski M, Hofmeister C, Le Coustumer P
University of Bordeaux 1, 33400 Talence, France.
Environ Sci Technol. 2006 Apr 1;40(7):2156-62. doi: 10.1021/es051498d.
Flow field flow fractionation (FIFFF), inductively coupled plasma-mass spectroscopy (ICP-MS), and transmission electron microscopy (TEM) coupled to X-ray energy dispersive spectrometry (X-EDS) are used in series for the first time to characterize colloids. Results demonstrate the utility of FIFFF-ICP-MS-TEM/X-EDS to relate physical properties (size) of colloids to their chemical properties (chemical composition, surface chemical composition, and colloids-trace elements association). Results suggest that the major part of natural organic matter (NOM) is concentrated in the fraction < 0.01 microm (C2). Aluminum, iron, and manganese are the main colloidal components in the fraction 0.01-0.45 microm (C1). Aluminum occurs as aluminum oxides or aluminosilicates in the whole size range, while iron and manganese occur as individual oxyhydroxides in the size range < 0.20 microm. Within the C2 fraction, Al, Mn, Cu, and Ni elements are complexed to NOM (e.g., humic substances). Iron is complexed to NOM in some samples and probably free in other samples. Lead is totally free in all samples. Within the C1 fraction, Cu and Pb are mostly associated to Fe and Mn oxyhydroxides. Consequently, NOM with Fe and Mn oxyhydroxides are the main colloidal carriers of trace elements in the Loire watershed system.
流场流分级分离法（FIFFF）、电感耦合等离子体质谱法（ICP-MS）以及与X射线能量色散光谱法（X-EDS）联用的透射电子显微镜法（TEM）首次被串联使用来表征胶体。结果证明了FIFFF-ICP-MS-TEM/X-EDS在将胶体的物理性质（尺寸）与其化学性质（化学成分、表面化学成分以及胶体-微量元素关联）联系起来方面的实用性。结果表明，天然有机物（NOM）的主要部分集中在<0.01微米的级分（C2）中。铝、铁和锰是0.01-0.45微米级分（C1）中的主要胶体成分。在整个尺寸范围内，铝以氧化铝或铝硅酸盐的形式存在，而在<0.20微米的尺寸范围内，铁和锰以单个羟基氧化物的形式存在。在C2级分中，铝、锰、铜和镍元素与NOM（如腐殖质）络合。在一些样品中铁与NOM络合，而在其他样品中可能是游离的。在所有样品中铅都是完全游离的。在C1级分中，铜和铅大多与铁和锰的羟基氧化物相关联。因此，含有铁和锰羟基氧化物的NOM是卢瓦尔河流域系统中微量元素的主要胶体载体。
