【摘要】 利用乳化剂聚乙二醇辛基苯基醚(乳化剂OP)胶束对二乙基二硫代氨基甲酸钠(DDTC)与铜(Ⅱ)显色反应增溶、增敏作用,建立了分光光度法测定水相体系中微量铜(Ⅱ)的新方法.研究表明,在pH=10的介质中,铜(Ⅱ)与DDTC及乳化剂OP形成的络合物,λmax=454 nm,摩尔吸光系数ε=1.2×104,铜含量在0~2.8μg/mL范围内线性关系良好(R=0.999 7).用该法测得大豆中的铜平均质量浓度为0.902μg/g,加标回收率为99.50%~100.80%,RSD为0.37%(n=6),结果令人满意.更多还原

【Abstract】 The paper uses the enhanced sensitivity effect of OP on the color reaction of DDTC and Cu(Ⅱ),and the spectrophotometry method to determine trace copper in water.The results showed that Cu(Ⅱ) reacted with DDTC and OP to form a green blue complex in the buffer solution at pH 10.0.The maximum absorption wavelength was 454 nm.The apparent molar absorptivity was 1.2 ×104.The absorbance showed good linearity with Cu(Ⅱ) in the range of 0~2.8 μg/mL,and the correlation coefficient was 0.999 7.The proposed method has been applied to the determination of Cu in Soybean samples.The average content of Cu in Soybean was 0.902 μg/g with the recovery of 99.50%~100.80%,and the relative standard deviation of 0.37(n=6).The results were satisfactory.更多还原