Determination of Melamine Residue in Egg by High-performance Liquid Chromatographic Method-Tandem Mass Spectrometry

[Objective]An high-performance liquid chromatographic method with tandem mass spectrometry(HPLC-MS/MS) was developed for the determination of melamine residues in eggs.[Method]The melamine residue was extracted with 1% trichloroacetic acid-methanol(V/V=1∶1),and cleaned-up with PCX solid phase extraction column.The solution was separated on a RP-HPLC column and detected by HPLC-MS/MS with positive electrospray ionization(ESI+) in multiple reaction monitoring(MRM) mode.Quantitation was carried out using an external standard method.[Result]The standard curves for all compounds were linear over the concentration range of 20-400 μg/kg with correlation coefficients(r2) of 0.998 5;The recoveries of melamine from egg samples spiked with the concentration levels at 50,100,200 μg/kg were range of 87.0%,96.8% and 94.4%.The limit of detection for the method was 3 μg/kg.The limit of quantification for the method was 10 μg/kg.[Conclusion]The established method was of simplicity,rapidity,high sensitivity,good reproducibility and better selectivity,which was quite fit for identification and determination of melamine in eggs.