Ionic liquid/Ammonium Sulfate Aqueous Two-phase System Coupled with HPLC Extraction of Sulfadimidine in Real Environmental Water Samples

Abstract

Room temperature ionic liquids are novel solvents with a rather specific blend of physical and solution properties that make them of interest for applications in separation science. In this study, a green, simple, and sensitive sample pretreatment procedure coupled with high-performance liquid chromatography (HPLC) was developed for the analysis of sulfadimidine (SM2) that exploits an aqueous two-phase system based on 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF4) and ammonium sulfate ((NH4)2SO4) using a liquid–liquid extraction technique in real environmental water samples. The influences of the concentration of (NH4)2SO4, pH value, temperature, and concentration of SM2 on the extraction efficiency of SM2 were determined. Under optimal conditions, the extraction efficiencies of SM2 were over 93.7%. Calibration curves yielded good linearity (R 2 = 0.9998) over the range 3–240 ng mL−1, and the limit of detection and limit of quantification for analytes were 0.9 ng mL−1 and 3 ng mL−1, respectively. The proposed method was successfully applied to the quantification of SM2 in water samples and recoveries were in the range of 101.2–107%.