Chemistry Department, Yasouj University, Yasouj 75914-353, Iran.
Food Chem Toxicol. 2010 Mar;48(3):891-7. doi: 10.1016/j.fct.2009.12.029. Epub 2010 Jan 6.
A simple and selective method for the determination of Cu(2+), Zn(2+) and Mn(2+) ions in real samples by FAAS after solid-phase extraction was developed. The method is based on the sorption of metal ions on Amberlite XAD-16 modified by 3-((2,6-dichlorophenyl)(1H-indol-3-yl)methyl)-1H-indole (DCPIMI) at a pH of 5.0. The metal ions retained on solid phase by complexation with ligand were then eluted with 6 mL of 4 mol L(-1) nitric acid in acetone. In order to obtain a reversible uptake and elution of metal ions, the influence of flow rates of eluent and sample solution, ligand concentration and amount of surfactant and condition of elution solution was also investigated. A preconcentration factor of 225 was achieved by passing 1350 mL of sample through the solid phase, while the limit of detection (LOD) of Cu(2+), Zn(2+) and Mn(2+) ions were found to be 1.9, 1.5 and 2.6 ng mL(-1), respectively, and the corresponding precision at 20 microg L(-1) was 2.1%, 2.3%, 3.0%.
建立了一种用 FAAS 在固相萃取后直接测定实际样品中 Cu(2+)、Zn(2+)和 Mn(2+)的简单、选择性方法。该方法基于在 pH 5.0 时，用 3-((2,6-二氯苯基)(1H-吲哚-3-基)甲基)-1H-吲哚(DCPIMI)修饰的 Amberlite XAD-16 吸附金属离子。然后，通过与配体络合，将金属离子保留在固相上，再用 6 毫升 4 mol L(-1)硝酸在丙酮中洗脱。为了获得金属离子的可逆吸附和解吸，还考察了洗脱液和样品溶液的流速、配体浓度和表面活性剂的用量以及洗脱液条件的影响。通过使 1350 毫升样品通过固相，实现了 225 倍的浓缩因子，而 Cu(2+)、Zn(2+)和 Mn(2+)离子的检出限（LOD）分别为 1.9、1.5 和 2.6 ng mL(-1)，相应的 20 microg L(-1)的精密度为 2.1%、2.3%和 3.0%。
