2,4—二氯苯基荧光酮分光光度法测定微量铜(Ⅱ)

SPECTROPHTOMETRIC DETERMINATION OF TRACE COPPER WITH 2,4-DICHLOROPHENYLFLUORONE

在弱酸性(pH=5.5)介质中和表面活性剂CTMAB存在的条件下,2,4-二氯苯基荧光酮与Cu(Ⅱ)形成稳定的三元络合物,可用分光光度法测定微量Cu(Ⅱ).其最大吸收波长λmax为600nm,表观摩尔吸光系数ε为1.10×105L·mol-1·cm-1,铜(Ⅱ)在0～0.6mg·L-1范围内符合Beer定律,用拟定方法测定了芝麻、茄子中铜(Ⅱ)的含量,结果较满意.

In the presence of buffer solution of pH=5.5 and CTMAB,Cu(Ⅱ) reacts rapidly with 2,4-Dichlorophenylfluorone to form a ternary micelle complex whose maximum absorption is at 600?nm and molar absorptivity is 1.10×105?L·mol-1·cm-1.Beer law is obeyed for 0～0.6?mg·L-1 Cu(Ⅱ).The method has been applied to the determination of trace Cu(Ⅱ) in sesame and Solanum melongena.The results are relatively satisfactory.