分散液相微萃取-气相色谱法检测尿中的三种苯并二氮杂类药物

Determination of benzodiazepines in urine by dispersive liquid-liquid microextraction coupled with gas chromatography

建立了分散液相微萃取与气相色谱电子捕获法检测尿中三种苯并二氮杂类药物的方法。对影响萃取富集效率的因素进行优化,萃取条件选定为:将0.75 mL含有35μL氯苯的甲醇混合溶液快速注入到5.0 mL样品溶液中,分散混匀后,以4000 r/min离心4 min,吸取有机相直接进样分析。在优化条件下,三种药物在1～400μg/L范围内均有良好的线性关系,r为0.9981～0.9990,检出限为0.33～0.66μg/L(S/N=3),RSD<3.9%(n=5),富集倍数231～242倍。该方法应用到人尿中3种苯并二氮杂类药物的检测,平均加标回收率在90.3%～92.8%之间,RSD在4.4%～7.6%之间。方法可满足生物样品中苯并二氮杂类药物的检测要求。

A novel method was developed for the pre-concentration and determination of benzodiazepines in urine by dispersive liquid-liquid microextraction（DLLME） coupled with capillary gas chromatography with electron capture detection（GC-ECD）.Parameters affecting extraction efficiency were investigated and optimized.In the method,0.75 mL of methanol containing 30.0 μL of chlorobenzene was rapidly injected into a 5.0 mL of urine sample.After centrifugation at 4000 r/min for 4 min,the sediment phase（chlorobenzene） was directly injected into the GC column for analysis.Under optimum conditions,linearity of the method was observed for all target analytes in the range from 1 to 400 μg/L with the correlation coefficients（r） ranging from 0.9981 to 0.9990.The LODs（S/N = 3） were estimated to be in the range from 0.33 to 0.66 μg/L.Excellent repeatability of the extraction（RSD≤3.9%,n = 5） was achieved.As high as 231 to 242 fold enrichment factors were achieved.The feasibility of this method was demonstrated by analyzing urine samples with spiked recoveries in the range of 90.3%~92.8%（RSD≤7.6%,n = 5）.The method was proven to be simple and environmental benign with high enrichment factor and low cost.