Abstract:

A high performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the quantification of melamine (MEL) and cyanuric acid (CYA) in chicken tissues. A sample preparation procedure comprising extraction with acetonitrile mixed with water at a ratio of 70:30 (V/V), the removal of lipids with n-hexane, centrifugation at 7000 r/min, thorough mixing of the supernatant and acetonitrile (1:1, V/V), centrifugation at 10000 r/min for the precipitation of protein and filtration through a 0.22μm membrane but excluding clean-up was used prior to HPLC-MS/MS analysis, resulting in a great reduction of the time required for sample preparation. Multiple reaction monitoring (MRM) mode was selected and internal standard isotope dilution method was used for quantification in order to improve the accuracy and quantitative linearity of the method. Calibration curves for MEL and CYA exhibited good linearity over the concentration range from 1 to 500 ng/mL, with R2 values of both larger than 0.999. Average recoveries ranged from 87.76% to107.89% for MEL and from 87.31% to 106.05% for CYA, with relative standard deviations (RSDs) ranging from 0.58% to 2.78% for MEL and from 1.26% to 4.33% for CYA at the spike levels of 0.1, 1 mg/kg and 5 mg/kg. The limits of detection (LOD) of MEL and CYA were 4 ng/kg and 2 ng/g, respectively. Therefore, this method is simple, rapid and accurate and is most suitable for the quantification of MEL and CYA in chicken tissues.

Key words: HPLC-MS/MS, melamine, cyanuric acid, chicken tissue