新试剂8Q5 SAH双波长增敏法测定铜

DETERMINATION OF COPPER USING DUAL-WAVELENGTH INCREASING SENSITIVITY METHOD WITH A NEW REAGENT 8Q5SAH

建立新试剂２－（８’－羟基喹啉－５’－磷酸偶氮）－１－羟基－８－氨基－３，６－萘二磺酸（简称８Ｑ５ＳＡＨ）测定铜的方法．实验表明，铜与试剂在 ｐＨ９．２３的 ＮＨ４Ｃ１／ＮＨ３·Ｈ２Ｏ 缓冲介质中发生配合反应形成１：６的配合物，表面活性剂十二烷基苯磷酸钠对体系有增敏作用，以试剂的最大吸收波长６４０ｎｍ为参比波长，以配合物的最大吸收波长 ５５０ｎｍ为测量波长，用双波长增敏法测得该体系的摩尔体系的摩尔吸光系数为２．９×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，线性范围为０－３５μｇ／２５ｍＬ，方法用于测定实际样品中的铜，结果满意．

A new method for determination of Copper using 2 - (8' - hydroxy quinoline - 5' - sulfoacid - 7 -azo) - 1 - hydroxy - 8 - amino - 3,6 - naphthalene disulfoacid is put forward. In pH9 .23 NH4Cl/ NH3· H2O media, Copper and 8Q5SAH react to form a 1: 6 complex; and the surface active agent DBS has effect of increasing sensitivity. The maximum absorbance of the reagent is 640 nm; the complex is 540 nm; the apparent molar absorptivity is 2. 9 × 104 L· mol - 1. cm - 1 by using the dual - wavelength increasing sensitivity method. Beer's law is obeyed in 0 - 35 μg/25 mL for copper. The method is applied to the determination of copper in actual samples with satisfactory results.