Ghaedi Mehrorang, Shokrollahi Ardeshir, Niknam Khodabakhsh, Niknam Ebrahim, Derki Somayyeh, Soylak Mustafa
Yasouj University, Chemistry Department, Yasouj, Iran 75914-353.
J AOAC Int. 2009 May-Jun;92(3):907-13.
A cloud point extraction (CPE) procedure was presented for the preconcentration of silver, zinc, and lead ions in various samples. The complexes of these metal ions with 2-(((1H-benzo[d]imidazol-2-yl)methoxy)methyl)-1H-benzo[d]imidazole (BIMMBI) are quantitatively extracted into the Triton X-114-rich phase after centrifugation. A solution of 1.0 M HNO3 in methanol was added to the surfactant-rich phase as the effective eluant before analysis by flame atomic absorption spectrometry. The influence of effective parameters such as the concentrations of BIMMBI, Triton X-114, and HNO3, pH, bath temperature, centrifuge rate, and time on method sensitivity and efficiency was optimized. Detection limits of 2.8, 1.7, and 1.1 ng/mL for Pb2+, Ag+, and Zn2+, respectively, along with a preconcentration factor of 30 and enrichment factors of 33, 48, and 53 for Pb2+, Ag+, and Zn2+, respectively, were obtained. The present CPE method is suitable for accurate and precise determination of trace amounts of analyte ions in complex matrixes. The proposed CPE procedure was applied to the determination of these ions in biological, natural water, wastewater, soil, and blood samples.
提出了一种浊点萃取（CPE）方法，用于预富集各种样品中的银、锌和铅离子。这些金属离子与2-(((1H-苯并[d]咪唑-2-基)甲氧基)甲基)-1H-苯并[d]咪唑（BIMMBI）形成的配合物在离心后被定量萃取到富含Triton X-114的相中。在通过火焰原子吸收光谱法分析之前，向富含表面活性剂的相中加入1.0 M硝酸甲醇溶液作为有效的洗脱剂。优化了BIMMBI、Triton X-114和硝酸的浓度、pH值、浴温、离心速率和时间等有效参数对方法灵敏度和效率的影响。分别获得了Pb2+、Ag+和Zn2+的检测限为2.8、1.7和1.1 ng/mL，以及Pb2+、Ag+和Zn2+的预富集因子为30，富集因子分别为33、48和53。目前的CPE方法适用于准确、精确地测定复杂基质中痕量分析物离子。所提出的CPE方法应用于生物、天然水、废水、土壤和血液样品中这些离子的测定。
