在线净化-超高效液相色谱同位素稀释串联质谱法检测蜂蜜中硝基咪唑类及其代谢物的残留

摘要

建立了在线净化( TurboFlow, TF)-超高效液相色谱同位素稀释串联质谱法检测蜂蜜中硝基咪唑类及其代谢物(甲硝唑,羟基甲硝唑,二甲硝咪唑,羟基二甲硝咪唑,洛硝哒唑,异并硝唑,羟基异并硝唑,奥硝唑)的方法。以0.1％甲酸溶解样品后,进入TF-超高效液相色谱-串联质谱系统分析,以内标法定量。对影响净化的条件如TF净化柱、流动相、洗脱溶液等进行优化。确定以Cyclone-P为净化柱,Hypersil GOLD aQ为分析柱,乙腈-0.1％甲酸溶液为流动相,电喷雾正离子选择反应监测模式( ESI+)检测。结果表明,在0.1~50μg/L范围内,目标化合物线性关系良好(相关系数均大于0.997),其定量限如下：奥硝唑、异并硝唑为0.1μg/kg；甲硝唑、羟基甲硝唑、二甲硝咪唑、洛硝哒唑和羟基异并硝唑为0.2μg/kg；羟基二甲硝咪唑为1.0μg/kg。本方法在4个水平的添加回收率为73.7％~116.4％,RSD为1.1％~9.1％。本方法简便、快速、结果准确可靠,并成功应用于实际样品中硝基咪唑及其代谢物残留的测定。%A TurboFlow ( TF ) online purification-ultra performance liquid chromatography-tandem mass spectrometric method was developed for the determination of nitroimidazoles and their metabolites ( ornidazole, IPZ, MNZ, MNZOH, DMZ, RNZ, IPZOH and HMMNI) in honey. The honey sample was extracted by H2 O containing 0. 1% formic acid solution. Then, the extraction solution was analyzed by TF-UPLC-MS/MS. The main factors influencing the purification efficiency including TF column, mobile phases and elution solutions were optimized. The compounds were detected by selective reaction monitoring ( SRM) in positive ion mode electrospray ionization ( ESI+) . The linear range of the method ranged from 0 . 1 to 50μg/L for nitroimidazoles and their metabolites, with the correlation coefficient ( R2 ) of over 0. 997. The limits of quantification were 0. 1 μg/kg for ornidazole, IPZ, 0. 2 μg/kg for MNZ, MNZOH, DMZ, RNZ and IPZOH, and 1. 0 μg/kg for HMMNI, respectively. The recoveries were in the range of 73. 7% to 116. 4% at four spiked levels with the relative standard deviations ranged from 1. 1% to 9. 1% in honey samples. The results indicate that the developed method is simple, efficient and precise, and can be used for the determination of nitroimidazoles and their metabolites in the actual honey samples.