高效液相色谱-串联质谱法测定茶叶中唑螨酯、三唑酮、鱼藤酮、除虫脲及萎锈灵残留量

HPLC-MS/MS Determination of Fenpyroximate,Rotenone,Triadimefon,Diflubenzuron and Carboxin in Tea

提出了高效液相色谱-串联质谱法同时测定茶叶中5种农药,即唑螨酯、三唑酮、鱼藤酮、除虫脲和萎锈灵残留量的方法。样品经乙腈和固体硫酸镁及氯化钠提取,以Shiseido C18MGII色谱柱为分离柱,以不同体积比的乙腈和0.005mol·L-1乙酸铵溶液的混合液为流动相进行梯度洗脱。采用电喷雾正离子源多反应监测模式进行质谱测定。5种农药的质量浓度均在1.00~20.0μg·L-1范围内与其峰面积呈线性关系。方法的检出限(3S/N)为0.005 mg·kg-1。在0.005,0.010,0.020mg·kg-1 3个浓度水平上进行加标回收试验,回收率在88.2%~104%之间,测定值的相对标准偏差(n=10)在4.8%~13%之间。

A method of HPLC-MS/MS for the determination of 5pesticides,i.e.,fenpyroximate,rotenone,triadimefon,diflubenzuron and carboxin in tea was proposed.The sample was extracted with acetonitrile and solid MgSO4 and NaCl.Shiseido C18 MGII column was used as stationary phase,and mixtures of acetonitrile and0.005mol·L-1 ammonium acetate solution in different ratios were used as mobile phase in gradient elution.ESI+and multi-reaction monitoring were adopted in MS/MS.Linear relationships between values of peak area and mass concentration of the 5pesticides were kept in the same range of 1.00-20.0μg·L-1,with detection limits(3S/N)of 0.005mg·kg-1.Tests for recovery were made at the concentration levels of 0.005,0.010 and 0.020 mg·kg-1,giving values of recovery and RSD′s(n=10)in the ranges of 88.2%-104% and 4.8%-13%respectively.