MBTAMB与铁（Ⅱ）显色反应的研究及其应用

Study on the Color Reaction of MBTAMB with Iron(Ⅱ)

本文系统地研究了新试剂２－［２′－（６′－甲基苯并噻唑）偶氮］－５－二甲氨基苯甲酸（简称ＭＢＴＡＭＢ）与Ｆｅ（Ⅱ）的显色反应。试验表明，在非离子表面活性剂Ｔｒｉｔｏｎｘ－１００和无机盐ＮａＣｌ存在下，Ｆｅ（Ⅱ）与ＭＢＴＡＭＢ反应生成１：２的配合物，其λｍａｘ＝６４３ｎｍ，表观摩尔吸光系数为９．２４×１０４Ｌ·ｍｏｌ－１·ｃｍ－１。Ｆｅ（Ⅱ）在０～０．６４μｇ／ｍＬ范围内符合比尔定律。用于测定矿泉水和人发样品的微量铁，结果满意。

The color reaction of a new reagent,2-[2′-(6′-methylbenzothiazolyl)azo]-5-dimethylaminobenzoic acid(MBTAMB), with iron(Ⅱ)has been investigated. MBTAMB reacts with iron(Ⅱ)to form an 1 + 2 bluish violet complex in the presence of non-ionic surfactant Triton X-100 and NaCl at pH 5.7. The sensitivity of the color reaction is high. The apparent molar absorptivity is 9.24 ×104L·mol-1·cm-1at 643 nm, Beer′s law is obeyed in the range of 0～0.64 μg/mL for iron. Its color is stable for at least 24 h. The proposed method can be applied to the determination of trace iron in mineral water and human hair samples.