牛奶中4种安乃近代谢物的液相色谱-串联质谱分析

Liquid Chromatography Coupled with Tandem Mass Spectrometric Analysis of Four Dipyrone Metabolites in Milk

建立了牛奶中4种安乃近代谢物——4-甲酰氨基安替比林、4-乙酰氨基安替比林、4-氨基安替比林和4-甲基氨基安替比林的液相色谱-串连质谱(LC-M/MS)测定法。样品加入TRIS缓冲溶液后用乙腈提取,提取液经乙腈饱和过的正己烷脱脂净化,采用LC-MS/MS电喷雾正离子(ESI+)、多反应监测(MRM)模式检测,4-乙酰氨基安替比林、4-甲酰氨基安替比林和4-氨基安替比林采用外标法定量,4-甲基氨基安替比林采用内标法进行定量。4-甲酰氨基安替比林的检出限为0.24μg/kg,4-氨基安替比林的检出限为0.59μg/kg,4-乙酰氨基安替比林的检出限为0.20μg/kg,4-甲基氨基安替比林的检出限则为0.61μg/kg。在添加量5～20μg/kg范围内,4种安乃近的回收率在80.4%～97.9%范围内,相对标准偏差(RSD)均小于9%。

A liquid chromatography coupled with tandem mass spectrometric （LC-MS/MS） method was proposed for the determination of four dipyrone metabolites in milk,i.e.,4-methylaminoantipyrine （MAA）,4-formylaminoantipyrine （FAA）,4aminoantipyrine （AA）,4-acetylaminoantipyrine （AAA）.Samples were extracted with acetonitrile,and the resulting extract was then cleaned up/defatted with acetonitrile-saturated n-hexane and concentrated by rotary evaporation prior to LC-MS/MS with positive electrospray ionization （ESI） in the multiple reaction monitoring （MRM） mode.FAA,AAA and AA were quantified by the external standard method,while MAA by the internal standard method.The limits of detection of FAA,AAA,AA and MAA by the method were 0.24,0.20,0.59μg/kg and 0.61μg/kg,respectively.Mean recoveries in blank samples at three spike levels （5,10,20 μg/kg） ranged between 80.4% and 97.9%,with relative standard deviations less than 9% （n=10）.