Determination of Trimethoprim in Egg by High Performance Liquid Chromatography Tandem Mass Spectrometry
A method for the determination of trimethoprim residues in eggs by high performance liquid chromatography tandem mass spectrometry was developed.The egg samples were extracted by acetonitrile twice,determined by electrospray positive ion scanning and multi-reaction monitoring mode,and quantified by external standard method.The results showed that there was a good linear relationship between the concentration of trimethoprim in the range of 0.5 ng·mL-1 to 50.0 ng·mL-1,with a correlation coefficient above 0.99;the detection limit of the method was 1.0 μg·kg-1;at low,medium,and high spiked levels,the average recovery rate of trimethoprim ranged from 82.3%to 94.5%,with a relative standard deviation of 1.2%to 2.8%.This method is easy to operate,accurate in results,and suitable for batch detection of residues of trimethoprim in eggs,with good prospects for promotion.
trimethoprimegghigh performance liquid chromatography tandem mass spectrometry