基于离子液体的分散液液微萃取-柱前荧光衍生高效液相色谱法测定水样中8种磺胺类药物

建立了一种基于离子液体的分散液液微萃取技术结合柱前荧光衍生高效液相色谱(IL-DLLME-HPLC-FL)对8种磺胺类药物进行检测的方法,并成功应用于实际环境水样的分析。实验考察了萃取参数对磺胺萃取效率的影响及衍生产物的稳定性。最佳实验条件:以40 μL C₆MIM]PF₆]为萃取剂,0.1 mL丙酮为分散剂,对pH=4且不含NaCl的水溶液进行不超声的分散液液微萃取,并衍生化反应6 h。结果表明:在最佳实验条件下,该法在0.2~10 μg/L和10~500 μg/L两个浓度范围内线性良好,线性相关系数r ≥0.9989;检出限为0.08~0.5 μg/L (S/N=3)。对实验室自来水、湖水、珠江水、池塘水分别加标5、50、200 μg/L的回收率为87.2%~101.4%,相对标准偏差为3.7%~6.2%。该法环保、简便,可用于测定实际水样中磺胺类药物。

Combination of dispersive liquid-liquid microextraction based on ionic liquid and pre-column fluorescence derivatization-high performance liquid chromatography for determination of eight sulfonamides in water samples

Dispersive liquid-liquid microextraction based on ionic liquid coupled with high performance liquid chromatography (HPLC) and pre-column fluorescent derivatization method (IL-DLLME-HPLC-FL) was developed for the determination of eight sulfonamides (SAs). The influence of IL-DLLME parameters on extraction efficiency and the stability of derivatives of the eight SAs were investigated. The optimized experimental conditions were as follows: 40 μL C₆MIM]PF₆] as extraction solvent, 0.1 mL acetone as dispersion solvents; water sample with 0% NaCl (pH 4) was extracted by dispersive liquid-liquid microextraction without ultrasonic-assistance and then derivatized for 6 h. Under the optimized experimental conditions, the results indicated that the eight sulfanilamides showed good linearities when their mass concentrations were in 0.2-10 μg/L and 10-500 μg/L, and the linear correlation coefficients were no less than 0.9989. The detection limits ranged from 0.08 μg/L to 0.5 μg/L (S/N=3). The proposed method was applied to the analysis of four water samples from different sources (tap water, lake water, Pearl River water and pond water). The relative recoveries of the SAs spiked in water samples were 87.2%-101.4% with the relative standard deviations of 3.7%-6.2% at three different concentration levels of 5, 50 and 200 μg/L. It is a convenient, environmental friendly method for the routine analysis of SAs in water samples.