液相色谱-串联质谱法监测奶牛配合饲料中碘化酪蛋白  

Method development for monitoring iodinated casein in cow formula feed by liquid chromatography-tandem mass spectrometry

作　　者：王宗义[1] 贾昌喜[1] 陈湘宁[1] 韩涛[1] 黄漫青[1] 

机构地区：[1]北京农学院,农产品安全检测与控制北京市重点实验室,北京102206

出　　处：《分析试验室》2012年第11期100-103,共4页Chinese Journal of Analysis Laboratory

基　　金：北京农学院基础科学基金助项目(2067516001)资助

摘　　要：以一碘酪氨酸(MIT)和二碘酪氨酸(DIT)为标志物,建立了奶牛配合饲料中碘化酪蛋白(IC)的LC-MS/MS监测方法。样品经Ba(OH)2水解,IC释放MIT和DIT,再经Cleanert PAX小柱净化,ZORBAX Eelipse XDB-C18(3.5μm,2.1×150 mm)柱,0.1%乙酸水溶液(V/V)和甲醇为流动相,梯度洗脱分离,正电喷雾质谱多重反应监测(MIT:308.0>262.0,308.0>135.2.0;DIT:433.8>387.4,433.8>289.5)。通过对样品水解液中MIT、DIT的定性、定量分析及建立DIT与IC的定量关系,实现了对IC的监测,IC最低检出水平不大于20 mg/kg;在20～1000 mg/kg的范围内IC的回收率为85.0%～128.5%,相对标准差为4.6%～17%。A new method was developed for monitoring of iodinated casein （IC） in cow formula feed by liquid chromatography-tandem mass spectrometry with monoiodoamino acid （MIT） and diiodoamino acid （DIT） as markers. Sample was hydrolyzed with barium hydroxide; then MIT and DIT released from IC were cleaned up with Ceanert PAX cartridge, and were separated on a ZORBAX Eclipse XDB-Cls column （3.5 μm, 2. 1 × 150 mm） with water （containing 0. 1% of acetic acid, V/V） and methanol on a gradient eluting mode. Mass spectrometric detection was performed using ESI positive MRM mode （m/z 308.0 〉 262. 0 and 308.0 〉 135.2. 0 for MIT; m/z 433.8 〉 387.4 and 433.8 〉 289.5 for DIT）. IC in samples was monitored by qualitative and quantitative analysis of MIT and DIT in the hydrolysate and the quantitative relationship between DIT and IC. The lowest IC level detected was not more than 20 mg/kg; and recoveries of IC within a range of 20 - 1000 mg/kg were 85.0% - 128.5% with 4. 6% - 17% of RSD.

关 键 词：碘化酪氨酸 碘化酪蛋白 奶牛配合饲料 液相色谱-串联质谱 

分 类 号：O657.63[理学—分析化学]