摘要
采用超高效液相色谱-串联电喷雾四极杆质谱（负离子模式）在多反应监测（MRM）模式下测定了牛奶中12种糖皮质激素的残留。试样中加入pH5．20的醋酸盐缓冲溶液和甲醇，超声提取，以去除部分蛋白质，然后用正己烷脱脂，依次经HLB柱、硅胶柱和氨基柱等固相萃取柱浓缩和净化后，通过Waters ACQUITY UPLC^TM BEHC18色谱柱分离，以甲醇和含0．196甲酸的水为流动相进行梯度洗脱。在超高效液相色谱-质谱分析过程中以保留时间和离子对（母离子和两个碎片离子）信息比较进行定性，以母离子和响应值高的碎片离子进行定量。该法的检出限为0．02～0．38μg／kg，最低定量限为0．07～1．27μg／kg。添加水平为2μg／kg和0．4μg／kg时，12种糖皮质激素的加标回收率为59．3％～94．3％，相对标准偏差为3．5％～16．7％。
A comprehensive analytical method based on ultra performance liquid chromatography-electrospray tandem mass spectrometry （UPLC-MS/MS） with negative mode has been developed for the simultaneous determination of twelve glucocorticoids residues in milk. The multi-reaction monitoring mode was employed for the determination. Milk samples were extracted by sonication in a methanol/acetate buffer （pH 5.20） solution, and then defatted with nhexane. Sample concentration and purification were performed using Oasis HLB, Sep-pak silica and Sep-pak amino-propyl solid phase extraction cartridges. The separation was performed on a Waters ACQUITY UPLCTM BEH C18 column （ 100 mm × 1.0 mm i. d. , 1.7 μm） with gradient elution using methanol and water （ containing 0. 196 formic acid） at a flow rate of 0. 1 mL/min. Identification of the glucocorticoids was done using retention times and the distribution of diagnostic ion pairs. Quantification of the glucocorticoids was based on the peak areas of the parent ion and a fragment ion with a higher signal. The limits of detection （LOD） of the method were from 0. 02 to 0. 38 μg/kg and the limits of quantification （ LOQ ） ranged from 0. 07 to 1.27 μg/kg. Average recoveries for the twelve glucocorticoids （ spiked at the levels of 2 and 0.4 μg/kg） ranged from 59.3% to 94.3%, with relative standard deviations between 3.5% and 15. 7%. Routine tests showed that the method is fast, sensitive and specific for the determina- tion of glucocorticoids residues in milk.
出处
《色谱》
CAS
CSCD
北大核心
2006年第3期213-217,共5页
Chinese Journal of Chromatography
基金
北京市自然科学基金重点项目(No.7041004)
关键词
超高效液相色谱-串联质谱法
固相萃取
糖皮质激素
残留
牛奶
ultra performance liquid chromatography-electrospray tandem mass spectrometry （UPLC-MS/MS）
solid-phase extraction
glucocorticoids
residues
milk
