桑色素—乳化剂OP光度法测定微量铁

Spectrophotometric Determination of Trace Iron in The Presence of Morin and Emulsifier OP

研究了铁（Ⅲ）—桑色素—乳化剂ＯＰ体系的显色反应条件。结果表明，在ｐＨ４．１的乙酸—乙酸钠缓冲介质中，形成的橙黄色配合物最大吸收波长为４１８ｎｍ，表观摩尔吸光系数为６．４６×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，铁（Ⅲ）含量在０～１６μｇ／２５ｍＬ范围内符合比耳定律。

The optimum conditions of color reaction of Fe(Ⅲ) with morin are studied. In HAc-NaAc buffer medium of pH 4 1,Fe(Ⅲ) can react with morin to form a kind of orange-yellow complex in the presence of emulsifier OP.The apparent molar absorption coefficient is 6 46×10 4 L·mol -1 ·cm -1 at 418 nm wavelength. Beer's law is obeyed for Fe(Ⅲ) in the range of 0￣16 μg· (25ml) -1 .It has been used for trace iron determination of grain and water samples.