茶叶、茶鲜叶及茶汤中啶虫脒残留的检测

建立了茶叶、茶鲜叶、茶汤中的啶虫脒残留量的液相色谱检测方法。茶叶样品经乙腈提取,碱性NaCl饱和溶液萃取,Envi-Carb/NH2固相萃取柱净化,10 mL乙腈洗脱,液相色谱-紫外检测器检测,茶叶,茶鲜叶啶虫脒的添加浓度为0.1～1.0mg/kg时,其平均回收率为68.5%～103.6.0%,相对标准偏差(RSD)≤13.6%。茶汤啶虫脒的添加浓度为0.033～0.333 mg/L时,其平均回收率为:73%～103.8%,相对标准偏差(RSD)≤7.6%。用该方法最低检出浓度为分别为:0.07、0.09 mg/kg、0.002 mg/L,符合农药残留分析要求。该方法可用于茶叶中啶虫脒的常规检测和啶虫脒在茶叶生产中应用的安全性评价研究。

A Method for Determination of Acetamiprid Residue in Tea, Fresh Tea and Tea Infusion with HPLC-UV

An effective method was developed for analysis of acetamiprid residue in tea,fresh tea and tea infusion by high performance liquid chromatography(HPLC)with UV detector.Tea samples were extracted by acetonitrile and Nacl Alkaline saturated solution,then purified with the Envi-Carb/NH2 cartridge,finally eluted with 10ml acetonitrile.Imidcloprid recoveries in tea,fresh tea were in the range of 68.5%~103.6% with 0.1~1.0mg/kg acetamiprid and relative standard deviations(RSD).when acetamiprid content was 0.033~0.333mg/L in infusion,The recovery was 73%~103.8% with RSD less than 7.6%.Practical determination limit in tea,fresh tea and infusion respectively was 0.07mg/kg,0.09mg/kg and 0.002mg/L.the method is quick and effective.It can be used for routine monitoring of the acetamiprid residues and safety assessment research in the tea.