高效液相色谱法测定稻田中丙草胺残留

用二氯甲烷提取稻田水和水稻植株样品中的丙草胺，稻田土壤样品用二氯甲烷-甲醇混合溶剂（体积比为9∶1）提取，再用高效液相色谱仪测定。方法在0．02 mg/L～2．00 mg/L的范围内线性良好，相关系数为0．9998；稻田水、土壤，水稻植株中丙草胺的检出限分别为0．001 mg/L、0．005 mg/kg、0．01 mg/kg；对稻田水、土壤和水稻植株分别做3个浓度水平的加标回收试验，重复5次，平均回收率在75．5％～84．7％之间，测定结果的相对标准偏差为2．0％～10．5％。

Determination of Pretilachlor in Paddy Field by HPLC

Pretilachlor in paddy-field water and paddy rice samples were extracted with dichloromethane, while paddy-field soil samples were extracted with dichloromethane-methanol mixture（volume ratio is 9∶1 ）.The extracts were subsequently determined by high performance liquid chromatography.The results showed that the linearity of pretilachlor was favorable in a range between 0.02 mg/L and 2.00 mg/L,the correlation coefficient was 0.999 8.The detection limits of pretilachlor in paddy-field water,paddy-field soil and paddy rice were 0.001 mg/L,0.005 mg/kg and 0.01 mg/kg,respectively.The spiked recovery test of three concentration levels were done in paddy-field water,paddy-field soil and paddy rice,and repeated five times.The average recovery rate ranged from 75.5% to 84.7%.The relative standard deviations were between 2.0% and 10.5%.