Detection and identification of zeranol in chicken or rabbit liver by liquid chromatography-electrospray tandem mass spectrometry

• Published in: Journal of AOAC International Vol. 85; no. 4; p. 841
• Main Authors: Fang, Xiaoming, Chen, Jiahua, Guo, Dehua, Wang, Guoquan
• Format: Journal Article
• Language: English
• Published: England 01.07.2002
• Subjects: Animals; Chickens; Chromatography, Liquid - methods; Estrogens, Non-Steroidal - analysis; Estrogens, Non-Steroidal - chemistry; Estrogens, Non-Steroidal - metabolism; Food Contamination - analysis; Liver - chemistry; Rabbits; Spectrometry, Mass, Electrospray Ionization - methods; Zeranol - analysis; Zeranol - chemistry; Zeranol - metabolism
• ISSN: 1060-3271
• DOI: 10.1093/jaoac/85.4.841

A sensitive, specific, and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for detection and identification of zeranol in chicken or rabbit liver. A homogenized liver sample was hydrolyzed with beta-glucuronidase/arylsulfatase, and the hydrolysate was extracted with ethyl ether. The supernatant was evaporated to dryness, and the residue was dissolved in chloroform and re-extracted with sodium hydroxide. After acidification, the extract was cleaned up on a C18 solid-phase extraction cartridge and analyzed by electrospray LC-MS/MS in the negative ion mode. The multiple reaction monitoring transition from both m/z 321 to 277 and m/z 321 to 303 was monitored for confirmation, and the product ion of 277 was used for quantitation. Separation was performed on a Waters XTettra C18 column (50 x 2.1 mm, 3.5 microm) combined with a safeguard column (Symmetry C18, 20 x 3.9 mm, 5 microm), using a gradient elution with acetonitrile and 20 mM ammonium acetate. Calibration curves were prepared and good linearity was achieved over the concentration ranges tested. For all liver samples fortified at 3 different levels of 1, 5, and 50 microg/kg, the overall recoveries and relative standard deviations were in the range of 61-90 and 8-13%, respectively. The limit of quantitation based on the assay validation was 1 microg/kg. The method had been used on a routine basis for detection and identification of zeranol in liver samples.