Ehsan Sadia, Prasher Shiv O, Marshall William D
Department of Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, 21, 111 Lakeshore Road, Ste-Anne-de-Bellevue, Que., Canada H9X 3V9.
Chemosphere. 2007 May;68(1):150-8. doi: 10.1016/j.chemosphere.2006.12.018. Epub 2007 Jan 26.
This study evaluated the efficacy of a washing process with cyclodextrin in combination with ethylenediaminetetraacetate (EDTA) for the simultaneous mobilization of heavy metals and PCBs from a field contaminated soil. Ultrasonically aided mixing of the field contaminated soil with a combination of cyclodextrin solution (10%, w/v) and a sparing quantity (2 mmol) of EDTA, simultaneously mobilized appreciable quantities of PCBs and much of the analyte metal (Cd, Cr, Cu, Mn, Ni, Pb, Zn) burdens. Relative to the action of individual reagents, a combination of randomly methylated (RAMEB) or hydroxypropyl beta-cyclodextrin (HPCD) with EDTA did not alter the PCB extraction efficiency nor did the presence of cyclodextrin change the efficiency of mobilization of most heavy metals (Al, Cd, Cr, Fe, Mn, Ni, and Zn) but did increase the recovery of Cu and Pb modestly. Three sonication-washes with the same charge of reagents mobilized appreciable quantities of PCBs (40-76%) and quantitatively extracted the labile fraction of Cd, Cu, Mn, and Pb. RAMEB proved to be more efficient than HPCD for PCB extractions. Three successive extractions with a single charge of cyclodextrin mobilized almost as much PCB (RAMEB, 76%; HPCD, 40%) as did the companion extractions that used fresh reagents each time (RAMEB, 78%; HPCD, 42%). Collectively, these studies demonstrated that PCB compounds and selected heavy metals can be co-extracted efficiently from soil with three successive washes with the same washing suspension containing EDTA and cyclodextrin.
本研究评估了环糊精与乙二胺四乙酸（EDTA）联合使用的洗涤工艺从受污染农田土壤中同时去除重金属和多氯联苯的效果。将受污染农田土壤与环糊精溶液（10%，w/v）和少量（2 mmol）EDTA进行超声辅助混合，可同时去除大量的多氯联苯和大部分分析物金属（镉、铬、铜、锰、镍、铅、锌）。相对于单独试剂的作用，随机甲基化β-环糊精（RAMEB）或羟丙基β-环糊精（HPCD）与EDTA联合使用不会改变多氯联苯的提取效率，环糊精的存在也不会改变大多数重金属（铝、镉、铬、铁、锰、镍和锌）的去除效率，但会适度提高铜和铅的回收率。用相同剂量的试剂进行三次超声洗涤可去除大量的多氯联苯（40 - 76%），并定量提取镉、铜、锰和铅的不稳定部分。结果表明，RAMEB在提取多氯联苯方面比HPCD更有效。用单次剂量的环糊精进行三次连续提取所去除的多氯联苯量（RAMEB为76%；HPCD为40%）几乎与每次使用新鲜试剂进行的对照提取（RAMEB为78%；HPCD为42%）相同。总体而言，这些研究表明，使用含有EDTA和环糊精的相同洗涤悬浮液对土壤进行三次连续洗涤，可以有效地共提取多氯联苯化合物和选定的重金属。
