Tween 80-DDC水相直接光度法测定油脂中微量铜

Micellar Sensitized Absorptionphotometric Determination of Trace Copper in Edible oil

本文研究了在表面活性剂Tween80存在的情况下 ,铜试剂与铜的显色反应结果表明 ,在水相中Tween80对铜试剂与铜的显色反应具有强烈的增敏效应 ,对生成的铜试剂与铜的有色缔合物具有明显的增稳保护作用。利用Tween80的胶束增溶作用 ,建立了以Tween80—铜试剂水相光度法直接测定铜的新方法 ,并用于油脂中微量铜的测定 ,回收率及精密度都符合食品检测要求 ,测定结果与有机溶剂萃取法一致。

A new method for determination of copper(Ⅱ)is presented in this paper.The results show that in the presence of nonionic surfactant Tween 80 Cu(Ⅱ) reacts with DDC to form a yellow complex which is stable in water and has an absorption maximum at 460nm(∑=3.04×10 4L·mol -1 ·cm -1 ).Beer's law is obeyed in the range of 0-40μg/25ml for Cu(Ⅱ).In the presence of Tween 80 the method can be applied directly to determine trace copper in edible oil with satisfactory results without any separation.