Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC...Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.展开更多
目的采用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry,UPLC-Q/Orbitrap HRMS)技术建立全血中60种天然...目的采用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry,UPLC-Q/Orbitrap HRMS)技术建立全血中60种天然毒素的快速筛查方法。方法分析并记录60种天然毒素标准品的色谱和质谱信息,构建筛查数据库。全血用蛋白沉淀法配合超声辅助分散进行前处理,使用Hypersil GOLD^(TM)C_(18)色谱柱,以5 mmol/L甲酸铵水溶液(含0.1%甲酸)和乙腈为流动相进行梯度洗脱,在电喷雾电离正离子模式和全扫描/数据依赖二级扫描(Full MS/dd-MS^(2))模式下检测。基于构建的筛查数据库,采用TraceFinder软件实现全血中60种天然毒素的快速筛查。结果建立的全血中60种天然毒素的UPLC-Q/Orbitrap HRMS筛查方法,除氧化苦参碱(LOD为20ng/mL)和毒毛旋花子苷元(LOD为40ng/mL)外,其余58种天然毒素的LOD范围为0.05~5 ng/mL。结论该方法前处理简单、高效,可以实现对全血中60种天然毒素的快速筛查。展开更多
文摘Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.
