School of Chemistry and Environmental Sciences, Henan Normal University, Henan Key Laboratory for Environmental Pollution Control, Ministry of Education, Xinxiang 453007, China.
J Hazard Mater. 2011 May 15;189(1-2):48-53. doi: 10.1016/j.jhazmat.2011.01.123. Epub 2011 Feb 17.
This paper established a new, rapid and sensitive method for the determination of lead in water samples preconcentrated by dispersive liquid-liquid microextraction (DLLME) prior to atomic fluorescence spectrometry. Dithizone was used as the chelating agent. In the DLLME procedure, lead formed lead-dithizone complex and migrated into the carbon tetrachloride micro-droplets. Important factors that would affect the extraction efficiency had been investigated including the kind and volume of extraction solvent and dispersive solvent, sample pH, the amount of chelating agent, extraction time and centrifugation time. The results showed that the coexisting ions containing in water samples had no obvious negative effect on the determination of lead. The experimental results indicated that the proposed method had a good linear range of 0.01-100 ng mL(-1) (r(2) = 0.9990). The precision was 2.12% (RSD, n = 7) and the detection limit was 0.95 ng L(-1). Proposed method was validated with four real environmental samples and the results indicated that the proposed method was excellent for the future use and satisfied spiked recoveries were in the range of 92.9-97.4%.
本文建立了一种新的、快速灵敏的方法，用于测定经分散液液微萃取（DLLME）预浓缩后的水样中的铅，原子荧光光谱法。二硫腙用作螯合剂。在 DLLME 过程中，铅与二硫腙形成铅-二硫腙络合物并迁移到四氯化碳微滴中。研究了影响萃取效率的重要因素，包括萃取溶剂和分散溶剂的种类和体积、样品 pH 值、螯合剂用量、萃取时间和离心时间。结果表明，水样中含有的共存离子对铅的测定没有明显的负影响。实验结果表明，该方法具有良好的线性范围为 0.01-100ngml(-1)(r(2)=0.9990)。精密度为 2.12%（RSD，n=7），检测限为 0.95ngL(-1)。用四种实际环境样品对所提出的方法进行了验证，结果表明，该方法具有很好的应用前景，加标回收率在 92.9-97.4%范围内。
