浊点萃取石墨炉原子吸收光谱法测定宁夏枸杞中的镉和铅

提出了浊点萃取石墨炉原子吸收法同时测定宁夏枸杞中痕量镉和铅的方法。考察了pH值、表面活性剂和螯合剂的浓度、加热温度和时间等影响因素,在最佳条件下,镉和铅的检出限（3s/k）达到0.008μg/L和0.105μg/L;相对标准差（n=7）分别为1.90%和1.28%。对于10 mL样品溶液的富集倍数分别为13.6和10.4。应用该方法测定了宁夏枸杞中的镉和铅的含量,加标回收率分别96.0%~98.0%和95.5%~98.0%。

Determination of Lead and Cadmium in Lycium barbarum L by Graphite Furnace Atomic Absorption Spectrometry with Cloud Point Extraction

A method for simultaneous determination of trace amounts of cadmium and lead in Lycium barbarum L by graphite furnace atomic absorption spectrometry with cloud point extraction is proposed. The parameters affecting the cloud point extraction such as pH,concentration of surfactant and coordination complex,heating temperature and time were investigated. Detection limits for Cd and Pb were 0. 008 and 0. 105 μg /L,respectively. The relative standard deviations( RSD) for seven replicate determinations of Cd and Pb were 1. 90% and 1. 28%,with enhancement factors of 13. 6( Cd) and 10. 4( Pb) in 10 mL sample solution. The proposed method was successfully applied to the determination of lead and cadmium in the Lycium barbarum L with the recoveries of 96. 0%-98. 0%,and 95. 5%-98. 0%,respectively.