以l-辛基-3-甲基咪唑六氟磷酸离子液体([C8MIM][PF6])为萃取剂,利用温度驱动离子液体分散液-液微萃取技术,结合高效液相色谱(HPLC)同时测定环境水体中2种磺胺类化合物:磺胺间二甲氧嘧啶(sulfadimethoxine,SDM)和磺胺甲噁唑(sulfamethoxazole,SMZ).对影响萃取效果的一系列因素(萃取剂、分散剂、萃取剂和分散剂的体积、pH、温度、萃取时间、盐度和离心时间等)进行了优化,在最优条件下,该方法具有较宽的线性范围(2—200μg.L-1)、较低的检出限(SDM,1.22μg.L-1;SMZ,0.50μg.L-1)、良好的重现性(RSD:SDM,1.94%;SMZ,1.9%;n=7)和较高的准确性(回收率,SDM,88.7%;SMZ,101.3%;n=7).以该方法对几处环境水样进行测定,获得了良好的回收率(63.0%—124.0%;RSD:2.1%—4.9%;n=6).
In this study,1-octyl-3-methylimidazolium hexafluorophosphate() was selected as extraction solvent,and temperature-controlled ionic liquid dispersive liquid-liquid microextraction(TC-IL-DLLME) was introduced to analyze two sulfonamides(SAs),sulfadimethoxine(SDM) and sulfamethoxazole(SMZ),in environmental water by coupling with high performance liquid chromatography(HPLC).Several parameters that could affect extraction performance were optimized,including the type and volume of extraction and dispersive solvents,sample pH,salinity,temperature,extraction and centrifugation time.Under the optimized conditions,the established method offered good linear range(2—200 μg · L-1),low detection limits(SDM,1.22 μg · L-1;SMZ,0.50 μg · L-1),good reproducibility(relative standard deviation,RSD: SDM,1.94%;SMZ,1.90%;n=7),and good recoveries(SDM,88.7%;SMZ,101.3%;n=7).In addition,the method was applied to the determination of SAs in environmental water samples,and satisfactory recoveries were obtained(63.0%—124.0%;RSD,2.1%—4.9%;n=6),which confirmed that this method was reliable and could be widely used to determine SAs in aqueous system.