水中毒死蜱测定方法改进研究

Study on Improvement of Determination Method of Water Poisoning Ticks

对液-液萃取气相色谱法测定水中毒死蜱方法进行了改进,通过加入丙酮作为辅助萃取溶剂,显著提高了检测回收率和方法稳定性,此外通过改变进样方式,选用脉冲不分流进样,使进样体积至2.0μl,明显提高了毒死蜱的响应值。优化条件下,水样加标回收率为92.4%～108%,相对标准偏差为4.5%～5.2%(n=6),检出限可达到0.02μg/L。改进后的分析方法显著提高了其测定准确度、精密度等指标性参数,有利于更准确地测定地下水中毒死蜱。

The method of determination of chlorpyrifos in water poisoning by liquid-liquid extraction gas chromatography was improved,and the recovery rate and stability of the method were significantly improved by adding acetone as the auxiliary solvent.In addition,the pulse was not shunted into the sample by changing the sampling method.By increasing the sample volume to 2.0μl,the response value of chlorpyrifos was significantly increased.Under optimal conditions,the recovery rate of water sample calibration is 92.4%~108%,and the relative standard deviation is 4.5%~5.2%(n=6).The detection limit can reach 0.02μg/L.The improved analytical method has improved the index parameters such as accuracy,precision and so on,which is beneficial to the more accurate determination of groundwater poisoning tick.