5—(4—磺酸基苯偶氮)8—(2,4—二硝基苯氨基)喹啉测定食品中铜的研究应用

Study on Spectrophotometry Determination of Copper with 5-(4-Sulfophenylazo ) 8-(2,4-Dinitrophenylamino ) Quinoline and its Application

在弱碱性介质中 ,5— (4—磺酸基苯偶氮 ) 8— (2 ,4—二硝基苯氨基 )喹啉 (SPDNPAQ)与铜反应生成 2∶ 1紫红色络合物 ,体系 λmax=56 0 nm,ε=1.2 3× 10 5L· mol-1· cm-1。铜含量在 0～ 0 .4 mg/ L内符合比耳定律 ,方法用于一些生物样品和水样中铜的测定。

In weak alkaline medium ,5-(4-sulfophenylazo ) 8-(2,4-Dinitrophenylamino ) Quinoline(SPDNPAQ) can react with copper to form a 2∶1 stable complex.The molar absorptivity is 1.23×10\+5 L·mol\+\{-1\}·cm\+\{-1\} at 560 nm,Beer's law is obeyed in the range of 0～0.4 mg/L.This method can be applied to the determination of copper in food and water with satisfactory results.