Determination of Copper,Zinc,Iron and Manganese in Dairy Products by Flame Atomic Absorption Spectrometry

Conditions of FAAS determination of Cu,Zn,Fe and Mn in samples of dairy products were studied and optimized.Tests of interferences,accuracy and precision were also made.The sample was digested with an acid mixture of HNO3 and HClO4,the solution obtained was evaporated nearly to dryness.The salts were taken up with HNO3 solution (1+99),and ready for FAAS determinations.Good linearity were obtained for all the 4 elements,as shown by their regression equations and correlation coefficients.Samples of 3 kinds of dairy products were analyzed by the proposed method,giving RSD′s less than 3.5% and recoveries in the range of 93.0%-103.0%.