LC-APCI-MS/MS法同时测定尿液中的三聚氰胺和三聚氰酸

Objective: To establish a liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometric method (LC-APCI-MS/MS) for the determination of melamine and cyanuric acid in urine samples. Methods: Urine samples were mixed with isotopic labeled internal standards, 15N3-melamine and 13C3-cyanuric acid, and diluted with acetonitrile. After centrifugation and separated on a Waters XBridge(superscript TM) Amide column, the analytes were detected by APCI-MS/MS with the multiple reaction monitoring (MRM) mode, positive for melamine and negative for cyanuric acid. Results: Calibration curves were linear in the range of 20 ng/ml~1000 ng/ml for melamine and cyanuric acid, both with the correlation coefficient better than 0.995.The intra and inter-batch precision (RSD) both less than 10%, and the accuracies and recoveries were both in the range of 89.9%~111.2%. Conclusion: The method is simple, sensitive and specific for the quantitative determination of melamine and cyanuric acid in the urine.