基于轻质萃取剂的涡旋辅助分散液液微萃取-气相色谱法测定瓶装水中塑化剂

Determination of plasticizer in bottled water by low density solvent based vortex assisted dispersive liquid-liquid microextraction combined with gas chromatography

以密度比水小的溶剂为萃取剂,建立了涡旋辅助分散液液微萃取-气相色谱检测瓶装水中塑化剂的方法.传统分散液液微萃取技术一般采用密度大于水的有机溶剂为萃取剂.本方法以密度比水小的轻质溶剂正己烷-甲苯(1∶1,体积比)为萃取剂,乙腈为分散剂,涡旋辅助分散,离心后获得富集相,进行气相色谱检测,富集倍数高达171倍,具有良好的线性关系(相关系数为0.998 2~0.999 2)和精密度(3.1%~11.8%),以及较低的方法检出限(1.43~12.05μg/L),加标回收率为81.2%~107.8%.该方法简便,快速,环保,可以用于测定实际水样中塑化剂.

A novel method of low-density solvent-based vortex-assisted dispersive liquid-liquid microextraction(DLLME)was developed for determination of plasticizer in bottled water by gas chromatography-flame ionization detection(GC-FID).Conventional DLLME methods usually employ organic solvents heavier than water as the extraction solvents.On the contrary,in this proposed extraction procedure,a mixture of low-density extraction solvent(toluene and n-hexane with V/V=1∶1)and dispersive solvent(acetonitrile)was injected into the aqueous sample solution to form an emulsion with vortex dispersed mode.The upper layer was collected and analyzed by GC after centrifugation.The enrichment factor was as high as 171.Under the optimized conditions,the proposed method provided a good linearity(R 2=0.998 2~0.999 2)and the relative standard deviations(RSDs)were in the range of 3.1%~11.8%.The limits of detection(S/N=3)were in the range of 1.43~12.05μg/L and the recoveries at three spiked levels were in the range of 81.2%~107.8%.It is a convenient,speedy,and environmentally benign for the routine analysis of plasticizer in water samples.