快速溶剂萃取-凝胶渗透色谱净化-LC/MS/MS结合测定蜂花粉中硝基咪唑类药物

目的:建立了快速溶剂萃取-凝胶渗透色谱净化-LC/MS/MS测定蜂花粉中硝基咪唑类化合物的分析方法。方法:样品以乙酸乙酯为萃取溶剂经快速溶剂萃取仪萃取,凝胶渗透色谱(GPC)净化,采用Zorbax Eclipse Plus C₁₈色谱柱(2.1 mm×100 mm,3.5μm)分离,以0.15%甲酸溶液(A)-甲醇(B)为流动相,梯度洗脱(0~2 min,90% A;2~5 min,90% A→40% A;5~7 min,40% A→10% A;7~7.5 min,10% A→90% A;7.5~12.0 min,90% A),流速为0.3 mL·min^-1。质谱采用多反应监测正离子扫描模式,基质匹配标准曲线同位素内标法定量。结果:硝基咪唑类化合物在一定范围内(1.0~15.0 ng·mL^-1)线性良好,相关系数在0.9961~0.9982内;硝基咪唑类化合物检出限为1.5μg·kg^-1,定量限为5.0μg·kg^-1;加标5.0μg·kg^-1时回收率为98.0%~114.2%,10.0μg·kg^-1时回收率为93.5%~104.0%,20.0μg·kg^-1时回收率为93.6%~101.2%,RSD分别为2.3%~5.2%、1.0%~1.1%和0.3%~1.7%。结论:该方法自动化程度高、灵敏度高,定性和定量结果准确。

Objective:To develop a method based on accelerated solvent extraction and gel permeation chromatography for analysis of nitroimidazoles residues in bee pollen.Methods:Sample was extracted with ethyl acetate using accelerated solvent extraction and purified by gel permeation chromatography.The Agilent Zorbax Eclipse Plus C₁₈ column(2.1 mm×100 mm, 3.5μm) was adopted for the study.The mobile phase consisting of 0.15% formic acid solution(A) -methonal(B) with gradient elution(0-2 min, 90%A;2-5 min, 90%A→40%A;5-7 min, 40%A→10%A;7-7.5 min, 10%A→90%A;7.5-12.0 min, 90%A) at a flow rate of 0.3 mL·min^-1.Mass spectrometer was operated in the positive ion mode using select reaction monitoring.Matrix-matched calibration curve and isotope internal standard was used for quantitative analysis.Results:The linearity of the calibration curve was obtained from 1.0 to 15.0 ng·mL^-1 with correlation coefficient of 0.9961-0.9982.The limit of detection in the method was 1.5μg·kg^-1, and the limit of quantitation was 5.0μg·kg^-1.The average recoveries of nitroimidazoles at three levels of 5.0, 10.0 and 20.0μg·kg^-1 were in the range of 98.0%-114.2%, 93.5%-104.0% and 93.6%-101.2% respectively;the RSDs were 2.3%-5.2%, 1.0%-1.1% and 0.3%-1.7%.Conclusion:The established method is proved to be of high degree of automation, high sensitivity, and accuracy at both qualitative and quantitative analysis.