采用蛋壳膜固相萃取-高效液相色谱法测定除草剂R-精噁唑禾草灵的含量。优化的试验条件如下:① 固相萃取时间为80 min;② 洗脱剂甲醇的用量为1 mL;③ 样品溶液的酸度为pH 7;④ 样品溶液的体积为25~100 mL。以C18色谱柱为分离柱,以甲醇-水(80+20)混合液为流动相,在检测波长236 nm处进行测定。R-精噁唑禾草灵质量浓度在5.00~50.0 μg·L-1范围内与峰面积呈线性关系,方法检出限(3S/N)为1.2 μg·L-1。方法用于水样和小麦粉样品分析,加标回收率在75.4%~95.2%之间,测定值的相对标准偏差(n=5)在3.7%~5.8%之间。

HPLC with eggshell membrane solid phase extraction was applied to the determination of the herbicide R-fenoxaprop-p-ethyl. The optimized conditions found were as follows: ① time of solid phase extraction was 80 min; ② amount of methanol used as eluent was 1 mL; ③ acidity of sample solution was pH 7; ④ volume of sample solution was 25 to 100 mL. C18 chromatographic column was used as stationary phase, and a mixture of methanol and water (80+20) was used as mobile phase. UV-detection at 236 nm was adopted in the determination. Linear relationship between values of peak area and mass concentration of R-fenoxaprop-p-ethyl was kept in the range of 5.00-50.0 μg·L-1, with detection limit (3S/N) of 1.2 μg·L-1. The proposed method was applied to the analysis of samples of water and wheat powder, giving values of recovery and RSD′s (n=5) in the ranges of 75.4%-95.2% and 3.7%-5.8% respectively.