CTMAB有机溶剂增敏光度法测定核桃中微量铜

摘要

In acid medium with ethanol,copper（Ⅱ）、 PAN and cetyl trimethyl ammonium bromide（CTMAB） could form a stable multi-micelle complex with the maximum absorption wave length at 520 nm.Lambert-Beer law was well obeyed for the copper（Ⅱ） concentration in ranging of 2.0～60.0 μg/L.Regression equation was y=0.0059x＋0.0048,which with correlation coefficient r=0.9982 and the apparent molar absorptivity ε=2.0×104 L/mol/cm.The relative standard deviation was less than 2.50%.The proposed method was used in the determination of trace copper in food,and the results were in consistent with the results obtained by flame atomic absorption spectrometry.%呈酸性并溶有乙醇的介质中,铜（Ⅱ）、PAN和十六烷基三甲基溴化铵（CTMAB）形成稳定的多元胶束络合物,其最大吸收波长为520 nm。铜（Ⅱ）浓度在2.0～60.0μg/L范围内符合比尔定律,回归方程为y=0.0059x＋0.0048,相关系数r=0.9982,其摩尔吸光系数ε=2.0×104L/mol.cm。相对标准偏差（RSD）小于2.50%。用此法测定食品中微量铜,所得结果与火焰原子吸收分光光度法相符。