National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080, Pakistan.
J Anal Methods Chem. 2012;2012:713862. doi: 10.1155/2012/713862. Epub 2012 Nov 22.
Cloud point extraction (CPE) has been used for the preconcentration and simultaneous determination of cobalt (Co) and lead (Pb) in fresh and wastewater samples. The extraction of analytes from aqueous samples was performed in the presence of 8-hydroxyquinoline (oxine) as a chelating agent and Triton X-114 as a nonionic surfactant. Experiments were conducted to assess the effect of different chemical variables such as pH, amounts of reagents (oxine and Triton X-114), temperature, incubation time, and sample volume. After phase separation, based on the cloud point, the surfactant-rich phase was diluted with acidic ethanol prior to its analysis by the flame atomic absorption spectrometry (FAAS). The enhancement factors 70 and 50 with detection limits of 0.26 μg L(-1) and 0.44 μg L(-1) were obtained for Co and Pb, respectively. In order to validate the developed method, a certified reference material (SRM 1643e) was analyzed and the determined values obtained were in a good agreement with the certified values. The proposed method was applied successfully to the determination of Co and Pb in a fresh surface and waste water sample.
浊点萃取（CPE）已被用于新鲜和废水样品中钴（Co）和铅（Pb）的预浓缩和同时测定。在 8-羟基喹啉（oxine）作为螯合剂和 Triton X-114 作为非离子表面活性剂的存在下，从水样中萃取分析物。进行了实验以评估不同化学变量（例如 pH、试剂（oxine 和 Triton X-114）的量、温度、孵育时间和样品体积）的影响。在相分离之后，基于浊点，将富含表面活性剂的相用酸性乙醇稀释，然后通过火焰原子吸收光谱法（FAAS）进行分析。对于 Co 和 Pb，分别获得了 70 和 50 的增强因子以及 0.26μg/L（-1）和 0.44μg/L（-1）的检测限。为了验证所开发的方法，分析了认证参考物质（SRM 1643e），并且获得的测定值与认证值吻合良好。该方法成功地应用于新鲜地表水和废水样品中 Co 和 Pb 的测定。
