Rapid and selective screening of melamine in bovine milk using molecularly imprinted matrix solid-phase dispersion coupled with liquid chromatography-ultraviolet detection

A simple, convenient and high selective molecularly imprinted matrix solid-phase dispersion (MI-MSPD) using water-compatible cyromazine-imprinted polymer as adsorbent was proposed for the rapid screening of melamine from bovine milk coupled with liquid chromatography-ultraviolet detection. The molecularly imprinted polymers (MIPs) synthesized by cyromazine as dummy template and reformative methanol–water system as reaction medium showed higher affinity and selectivity to melamine, and so they were applied as the specific dispersant of MSPD to extraction of melamine and simultaneously eliminate the effect of template leakage on quantitative analysis. Under the optimized conditions, good linearity was obtained in a range of 0.24–60.0 μg g−1 with the correlation coefficient of 0.9994. The recoveries of melamine at three spiked levels were ranged from 86.0 to 96.2% with the relative standard deviation (RSD) ≤ 4.0%. This proposed MI-MSPD method combined the advantages of MSPD and MIPs, and could be used as an alternative tool for analyzing the residues of melamine in complex milk samples.

► A simple and rapid MI-MSPD method for determination of melamine from milk.
► Water-compatible MIP was obtained by cyromazine as dummy template in methanol–water solution.
► Rapid screening of melamine in milk, while interferences from milk matrix were eliminated.
► Extraction efficiency was markedly increased with reduced equilibrium time.
► This method improved the selectivity and eliminated the effect of template leakage on quantitative analysis.