超高效液相色谱法同时测定蜂蜜中双甲脒及其代谢物残留量

Simultaneous determination of amitraz and its metabolite(2,4-dimethylaniline)residues in honey by ultra-performance liquid chromatography

目的建立超高效液相色谱法(ultra-performance liquid chromatography,UPLC)同时测定蜂蜜中双甲脒及其代谢物(2,4-二甲基苯胺)残留量的方法。方法样品经0.1 mol/L NaOH溶液提取、正己烷-异丙醇(2:1,V:V)混合液萃取,再采用ACQUITYUPLC?BEHC18(2.1mm×100mm,1.7μm)色谱柱进行分离,以乙腈和20 mmol/L乙酸铵溶液作为流动相,柱温30℃、流速为0.20 mL/min,检测器波长在235 nm处进行检测,外标法定量。结果双甲脒及2,4-二甲基苯胺标准曲线在2.0~500.0 ng/mL范围内呈良好的线性关系,线性相关系数均大于0.999,方法检出限双甲脒为0.27μg/kg,2,4-二甲基苯胺为0.42μg/kg,以样品加标做回收率测定,双甲脒与2,4-二甲基苯胺的回收率分别为99.6%~101.2%和99.3%~101.6%,测得的相对标准偏差均小于5%。结论该方法具有线性范围宽、检出限低,灵敏度、准确度高,重复性好等优点,能满足于蜂蜜中双甲脒及2,4-二甲基苯胺的快速检测要求。

Objective To establish a method for the determination of amitraz and its metabolite(2,4-dimethylaniline)residues in honey by ultra-performance liquid chromatography.Methods The samples were diluted with 0.1 mol/L sodium hydroxide,extracted with n-hexane-isopropanol(2:1,V:V),and then separated by ACQUITY UPLC®BEH C18(2.1 mm×100 mm,1.7μm)with ammonium acetate(20 mmol/L)/Acetonitrile as the gradient eluent with a flow rate of 0.20 mL/min at 30℃.A diode array detector was used to detect at 235 nm.The external standard method was used for quantitative analysis.Results The standard curves of amitraz and 2,4-dimethylaniline of honey additives showed a good linear relationship in the range of 2.0~500.0 ng/mL,and the correlation coefficient was more than 0.999.The limit of detection for amitraz and 2,4-dimethylaniline were 0.27μg/kg and 0.42μg/kg,respectively.The recovery rates of spiked amitraz and 2,4-dimethylaniline were 99.6%~101.2%and 99.3%~101.6%,respectively.The relative standard deviations were less than 5%.Conclusion The method has the advantages of wide linear ragne,low detection limit,high sensitivity,high accuracy and good repeatability.It can meet the requirements for the determination of amitraz and 2,4-dimethylaniline in honey.