摘要
将超声波萃取（USE）与分散液-液微萃取（DLLME）联合,利用气相色谱-电子捕获检测（GC-ECD）,建立了一种高灵敏度检测水体中菌核净的新方法。对萃取的条件进行优化,选定萃取条件为：在5 mL样品中,注入1 mL丙酮和0.1 mL的四氯化碳混合液,20 Hz超声10 min,振荡混匀后高速离心5 min,移出下层溶剂低温吹干以丙酮定容自动进样分析。在优化条件下,样品的富集倍数可达50倍,检出限为0.001μg/mL,对采于蔬菜地边的水样进行加标回收率实验,平均回收率在81%以上,相对标准偏差在4.3%～7.6%之间,方法可满足水样中菌核净农药残留的检测要求。
A nove1 method was developed for the determination of dimethachlon by ultrasonic extraction（USE） with dispersive liquid-liquid microextraction（DLLME） coupled with capillary gas chromatography with electron capture detection（GC-ECD）.Some important parameters that influence the extraction efficiency,such as the kind of the extraction and disperser solvent,their volume and the extraction time were investigated.In the method,1.0 mL of acetone and 0.1 mL of carbon tetrachloride were rapidly injected into a 5.0 mL of sample, after 20 Hz ultrasonic vibration for 10 min and high speed centrifugation for 5 rain, shifted out the lower layer, blew dry at lower temperature, dissolved with ceaain volume acetone and automatically injected into the GC for analysis. Under the optimum conditions, as high as 50 fold enrichment factors were achieved with the detection limits of 0.001 μg/mL. The spiked recovery reached up to 81% and the relative standard deviations were between 4.3 % and 7.6 %. The method was proven to be simple and environmental benign with high enrichment factor and high sensitivity.
出处
《分析试验室》
CAS
CSCD
北大核心
2010年第1期111-114,共4页
Chinese Journal of Analysis Laboratory
关键词
超声波萃取
分散液-液微萃取
气相色谱
菌核净
Ultrasonic extraction
Dispersive
Liquid-liquid microextraction
Gas chromatography
Dimethachlon
