高效液相色谱法测定水中二甲戊乐灵

DETERMINATION OF TRACE PENDIMETHALIN IN WATER BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY.

目的：建立水样中二甲戊乐灵的高效液相色谱测定法。方法：样品经二氯甲烷液一液萃取。旋转真空蒸发浓缩后，用高效液相色谱法分离测定。分析条件为：色谱柱为C18柱（ODS），250×4．6mm，5μm；柱温；室温；流动相：85％甲醇-水；流速：1ml／min：检测波长：238nm。结果：本法线性范围上限至少为100ng；平均回收率为95，6％；日内相对标准偏差为0．48％～3．65％，方法检出限为4．7×10^-3μg/L。结论：本法具有前处理简单、灵敏度高、准确度好等优点，适合于水样中二甲戊乐灵的分析测定。

Objective： To establish a high performance liquid chromatographic method （HPLC） for the determination of trace pendimethalin in water. Method： After a liquid- liquid extraction of the target compound with dichloromethane, the extract was concentrated to a small volume by rotary vacuum evaporation, and then blown to dryness by gentle N2 stream. The residue was dissolved in 0.20ml of methanol, and pendimethalin in the samples was separated and quantified by HPLC- UV. The optimized chromatographic conditions were： analytical column, C18 column （250 × 4.6mm, 5μm,）; Column temperature, room temperature; mobile phase, methanol- water （85： 15） ; flow rate： 1 ml/min; UV detection wavelength： 238nm. Results： Calibration graph was linear up to at least 100ng. The average recovery of the method was 95.6%, the within - day relative standard deviation were 0.48% -3.65%, and the detection limit was 4.7 × 10^-3μg/L. Conclusion： The method is sensitive, accurate and suitable to the determination of trace pendimethalin in water samples.