高效液相色谱法测定鸡肝中玉米赤霉醇的残留量

Determination of Zeranol in Chicken Livers by High Performance Liquid Chromatography with Ultraviolet Detection

建立了高效液相色谱测定鸡肝中玉米赤霉醇的方法。样品经β 葡糖苷酸酶水解、乙醚提取、氢氧化钠抽提、C18小柱净化后,用ZorbaxSB Phenyl柱(250mm×4 6mmi.d.,5μm)分离,以乙腈 0 3%三氟乙酸水溶液(体积比为40∶60)作流动相,流速为0 80mL/min,于262nm波长处检测。结果表明,样品的加标平均回收率为72 0%～80 4%,相对标准偏差为8 3%～13 9%,定量测定低限(LOQ)为5μg/kg。方法已应用于实际样品的测定。另外,用高效液相色谱 质谱/质谱法对分离出的组分予以定性确证。

A high performance liquid chromatographic method (HPLC) was developed for the determination of zeranol in chicken livers. A homogenized liver sample was hydrolyzed with βglucuronidase and the hydrolysate was extracted with ethyl ether. The supernatant liquid was evaporated to dryness, and the residue was dissolved in chloroform and subsequently reextracted with a sodium hydroxide solution. After acidification, the extract was cleaned up on a C18 SPE cartridge. The chromatographic separation was performed on a Zorbax SBPhenyl column (250 mm×46 mm i.d., 5 μm) using acetonitrile03% trifluoroacetic acid (TFA) aqueous solution (40∶60, v/v) as mobile phase at a flow rate of 080 mL/min and UV detection at 262 nm. The extraction procedure was validated by analyzing samples spiked with zeranol at three different concentration levels of 5, 20 and 50 μg/kg. The average recoveries and the relative standard deviations were 720%-804% and 83%-139%, respectively. The method was also applied for the determination of real samples. Furthermore, the sample identification was confirmed by HPLCtandem mass spectrometry (MS/MS) analysis.