柱前衍生-固相萃取-高效液相色谱荧光法 测定蔬菜中草甘膦

Determination of glyphosate in vegetables by high performance liquid chromatography- fluorescence detection with pre-column derivatization and solid phase extraction

中文关键词:  柱前衍生  高效液相色谱法  草甘膦  蔬菜

英文关键词:pre-column derivatization  high performance liquid chromatography  glyphosate  vegetables

中文摘要:

      目的 建立快速、准确的蔬菜中草甘膦的柱前衍生-固相萃取-高效液相色谱荧光测定方法。方法 蔬菜提取液样经衍生后经固相萃取, 过C18色谱柱, 以甲醇-水(70:30, V:V) 为流动相, 流速1.0 mL/min, 柱温为35 ℃, 荧光检测激发波长为265 nm, 发射波长为315 nm。结果 草甘膦的加标回收率在89.2%~99.2%范围, 其相对标准偏差均<5.0%, 在0.5~20.0 ng/mL范围呈现良好的线性, 其回归系数>0.999, 最低定量检出限(LOQ) 为0.02 mg/kg。结论 本方法回收率高, 净化效果好, 杂质干扰少, 可满足蔬菜中痕量草甘膦的残留检测要求。

英文摘要:

      Objective To develop a method for the determination of glyphosate in vegetables by high performance liquid chromatography-fluorescence detection with pre-column derivatization and solid phase extraction. Methods The glyphosate was derived from water samples and cleaned up with solid phase extraction, and then the separation was performed on a C18 column by the mobile phase consisting of methanol-water (70:30, V:V) at the flow rate of 1.0 mL/min and the column temperature of 35 ℃. The fluorescence excitation and emission wave lengths were set at 265 nm and 315 nm, respectively. Results The recoveries of glyphosate were 89.4%~98.9%, and the RSDs were less than 5.0%. Calibration curve of glyphosate was linear within the range of 0.5~20.0 ng/mL with the regression coefficient greater than 0.999. The limit of quantification (LOQ) was 0.02 mg/kg. Conclusion This method has high recovery rates, good purification results and less impurity interference, and is suitable for the detection of trace glyphosate residue in vegetables.