高效液相色谱-串联质谱测定猪肉中3种β-受体激动剂残留量

建立一种同时测定猪肉中3种β-受体激动剂残留量的高效液相色谱-电喷雾串联质谱(HPLC-ESI-MS/MS)确证分析方法。样品经β-葡萄糖醛酸酶/芳基硫酸酯酶酶解、乙酸铵缓冲液提取和MCX固相萃取柱净化,采用Agilent ZorbaxSB-C18(2.1mm×150mm,3.5μm)色谱柱,0.1%的甲酸水溶液、甲醇和乙腈作为流动相进行洗脱,高效液相色谱分离,电喷雾离子源电离,正离子多反应监测模式进行检测,内标法定量。3种药物在0.05～1μg/kg浓度范围内线性良好,相关系数r均大于0.999,0.05、0.1、0.5μg/kg3个浓度水平的添加回收率在89.7%～106.7%之间,相对标准偏差为2.4%～8.6%,3种药物的定量限均为0.05μg/kg。方法适用于猪肉中β-受体激动剂残留的确证分析。

Determination of 3 beta-agonist residues in pork by high performance liquid chromatography-electrospray ionization tandem mass spectrometry

A confirmative method was developed by high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) to detect 3 beta-agonist residues in pork simultaneously, which included clenbuterol, ractopamine, salbutamol. In the method, The analytes were extracted with NH4Ac solution from homogenized samples and hydrolysised with beta-glucuronidase overnight at 37℃. Then the extract was filtered and the filtrate was cleaned by oasis MCX solid phase extraction cartridge. The HPLC separation was performed on an agilent zorbax SB-C_(18) column (2.1 mm×150 mm, 3.5 μm) utilizing a isocratic elution program of water (containing 0.1% formic acid), methanol and acetonitrile as the mobile phase. Identification and quantification were achieved by using HPLC-ESI-MS/MS in positive mode and multiple reaction monitoring (MRM) using internal standard method. Good linearities were observed in the range from 0.05 μg/kg to 1 μg/kg with correlation coefficients above 0.999. The method was validated at 0.05, 0.10 and 0.50 μg/kg. The validation results were as follows: the average recoveries of 3 beta-agonists ranged from 89 7% to 106.7% with the relative standard deviations of 2.4%～8.6%, quantification limits for the three analytes were all 0 05 μg/kg. With good reproducibility, high sensitivity, short analysis time and good determination capacity, the method could meet the requirements of both domestic and international legislation. The method is applicable to simultaneous confirmation of multi-residues of 3 beta-agonists in pork.