多壁碳纳米管结合气相色谱-电子捕获检测法同时测定茶叶中18种有机氯类农药残留

Simultaneous determination of 18 kinds of organochlorine pesticide residues in tea by multi walled carbon nanotubes combined with gas chromatograph-electron capture detection

中文关键词:  有机氯农药  多壁碳纳米管  气相色谱法  电子捕获检测器  茶叶  QuEChERS

英文关键词:organochlorine pesticide  multi walled carbon nanotubes  gas chromatography  electron capture detector  tea  QuEChERS

中文摘要:

      目的 建立多壁碳纳米管(multi walled carbon nanotubes, MWCNTs)结合气相色谱-电子捕获检测法(gas chromatography-electron capture detection, GC-ECD)同时测定茶叶中18种有机氯农药残留的分析方法。 方法 样品经丙酮提取, 基于MWCNTs改良QuEChERS方法净化, Rtx-5色谱柱分离, 电子捕获检测器检测, 基质外标法定量。结果 18种有机氯农药在0.01~0.10 μg/mL范围内具有良好的线性关系, 相关系数(r)均大于0.99; 3个添加水平下的平均回收率为85.2%~119.9%, 相对标准偏差(relative standard deviations, RSDs)为0.61%~6.77% (n=6)。方法检出限为10~18 μg/kg, 定量限为15~23 μg/kg。结论 该方法操作简单、准确度和精密度好, 为茶叶中有机氯类多农药残留快速分析提供了新方法。

英文摘要:

      Objective To establish a method for the simultaneous determination of 18 kinds of organochlorine pesticide residues in tea by multi walled carbon nanotubes (MWCNTs) combined with gas chromatograph-electron capture detector (GC-ECD). Methods The samples of tea were extracted with acetone, cleaned up with the improved QuEChERS based on MWCNTs, separated by the Rtx-5 column, detected by electron capture detector, and quantified by the matrix external standard method. Results Under the optimal experimental conditions, good linear relationships were observed for all pesticides in the range of 0.01 to 0.10 μg/mL, the correlation coefficients (r) of the calibration curves were greater than 0.99, the average recoveries of all pesticides ranged form 85.2% to 119.9% at 3 spiked leves, and the relative standard deviations (RSDs) (n=6) were 0.61%?6.77%. The limits of detection and the limits of quantification were 10?18 μg/kg and 15?23 μg/kg, respectively. Conclusion The method has the advantages of simple operation, good accuracy and precision, and it provides a new method for the rapid analysis of organochlorine pesticide residues in tea.