光度法测定食品中痕量铝——用对乙酰基偶氮氯膦作显色剂  

Photometric Determination of Traces of Aluminum in Foodstuffs With p-Acetylchlorophosphonazo as Color Reagent

作　　者：于辉[1] 翟庆洲[1] 胡伟华[1] 田丽霞[1] 

机构地区：[1]长春理工大学纳米技术研究中心,长春130022

出　　处：《理化检验（化学分册）》2008年第1期28-29,32,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：在pH4．3乙酸-乙酸钠缓冲体系中，对乙酰基偶氮氯膦与铝（Ⅲ）形成1：1蓝紫色络合物，最大吸收波长为604nm，表观摩尔吸光率ε604nm=9．92×10^3L·mol^-1·cm^-1,铝（Ⅲ）的质量浓度在0．60mg·L^-1以内遵守比耳定律。方法用于方便面、面包及梨中痕量铝的测定，测定结果的相对标准偏差（n=7）在1．03％～2．16％之间，回收率试验的结果在96．5％～101．0％之间。In an acetate buffer medium of pH 4. 3, a blue-violet complex was formed by the reaction of Al（Ⅲ） with p-acetylchlorophosphonazo （abbreviated as CPA-pA） with its molar ratio of 1 to 1. Absorption maxima of the complex was found at the wavelength of 604 nm and its apparent molar absorptivity was 9. 92×10^3L·mol^-1·cm^-1. Beer＇s law was obeyed over the range within 0. 60 mg· L^-1 of aluminum（Ⅲ）. The proposed method has been applied to the determination of aluminum in 3 samples of foodstuff, RSD＇s （n=7） values calculated from the analytical results were in the range from 1.03% to 2.16%, and values of recovery found were in the range of 96.5% to 101.0%.

关 键 词：光度法 对乙酰基偶氮氯膦 铝 食品 

分 类 号：O657.32[理学—分析化学]