Fluorophotometric Determination of Melamine in Feed Based on the Formation of the Complex Among Melamine Copper(Ⅱ) and Bovine Serum Albumin

In a Tris-HCl buffer solution of pH 7.1, and under the chelate-bridging action of Cu(Ⅱ)-ion, a ternary complex among melamine, Cu(Ⅱ) and BSA was formed, leading to enhancement of fluorescence quenching of BSA. Linear relationship between values of relative fluorescence intensity and concentration of melamine was kept in the range of 1×10-5-1×10-6mol·L-1, with detection limit (3s/k) of 2.50×10-7mol·L-1. On the base of feed samples, test for recovery was made by standard addition method; values of recovery found were in the range of 96.0%-108% with RSD′s (n=6) in the range of 0.8%-2.8%.