中空纤维液相微萃取-高效液相色谱法测定水中3种除草剂残留量

HPLC Determination of Residual Amounts of 3 Herbicides in Water with Hollow Fiber Liquid Phase Microextraction

应用中空纤维液相微萃取-高效液相色谱法测定水中二氯喹啉酸、特丁噻草隆、戊炔草胺等3种除草剂的残留量。样品以聚丙烯中空纤维为支撑,正辛醇萃取,以600r·min-1转速在40℃的条件下萃取20min。所得净化液以Inertsil ODS-SP C18色谱柱为分离柱,以甲醇-水(82+18)混合液为流动相,在检测波长220nm处进行测定。3种除草剂在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.20~0.35μg·L-1之间。以地表水样为基体进行加标回收试验,所得回收率在90.6%~106%之间。方法的相对标准偏差(n=6)在3.1%~6.8%之间。

HPLC was applied to the determination of residual amounts of 3herbicides,i.e.quinclorac,tebuthiuron and propyzamide in water with hollow fiber liquid phase microextraction.The sample was extracted with N-octanol using polypropylene hollow fibrous membranes.The extraction was carried out for 20 min at the rate of600r·min-1 at 40℃.Inertsil ODS-SP C18 chromatographic column was used as stationary phase,and a mixture of methanol and water(82+18)as mobile phase.UV-detection at 220 nm was adopted in the determination.Linear relationships between values of peak area and mass concentration of the 3herbicides were kept in definite ranges.Detection limits(3S/N)found were ranged from 0.20 to 0.35μg·L-1.On the sample of surface water,test for recovery was made by standard addition method;values of recovery found were in the range of 90.6%-106%.RSD′s(n=6)of the method found were in the range of 3.1%-6.8%.