Multiple functional ionic liquids based dispersive liquid-liquid microextraction combined with high performance chromatography for the determination of phenolic compounds in water samples.
A new mode of ionic liquid based dispersive liquid-liquid microextraction (IL-DLLME) is developed. In this work, [C6MIm][PF6] was chosen as the extraction solvent, and two kinds of hydrophilic ionic liquids, [EMIm][BF4] and [BSO3HMIm][OTf], functioned as the dispersive solvent. So in the whole extraction procedure, no organic solvent was used. With the aid of SO3H group, the acidic compound was extracted from the sample solution without pH adjustment. Two phenolic compounds, namely, 2-naphthol and 4-nitrophenol were chosen as the target analytes. Important parameters affecting the extraction efficiency, such as the type of hydrophilic ionic liquids, the volume ratio of [EMIm][BF4] to [BSO3HMIm][OTf], type and volume of extraction solvent, pH value of sample solution, sonication time, extraction time and centrifugation time were investigated and optimized. Under the optimized extraction conditions, the method exhibited good sensitivity with the limits of detection (LODs) at 5.5 μg L(-1)and 10.0 μg L(-1) for 4-nitrophenol and 2-naphthol, respectively. Good linearity over the concentration ranges of 24-384 μg L(-1) for 4-nitrophenol and 28-336 μg L(-1) for 2-naphthol was obtained with correlation coefficients of 0.9998 and 0.9961, respectively. The proposed method can directly extract acidic compound from environmental sample or even more complex sample matrix without any pH adjustment procedure.
Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People׳s Republic of China; Graduate University of Chinese Academy of Sciences, Beijing 100039, People׳s Republic of China.
Jian-Nan
JN
Sun
Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People׳s Republic of China. Electronic address: chenjuan@licp.cas.cn.
Juan
J
Chen
Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, People׳s Republic of China. Electronic address: shiyp@licp.cas.cn.
Yan-Ping
YP
Shi
D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007477:Ions; D057230:Limit of Detection; D059627:Liquid Phase Microextraction; D009284:Naphthols / Q000032:analysis; D009596:Nitrophenols / Q000032:analysis; D019800:Phenol / Q000032:analysis*; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D014465:Ultrasonics; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis
D007220:Industrial Waste; D007477:Ions; D009284:Naphthols; D009596:Nitrophenols; D012997:Solvents; D014874:Water Pollutants, Chemical; D014867:Water; D019800:Phenol; C028405:2-naphthol; C024836:4-nitrophenol
Dispersive liquid–liquid microextraction; Environmental water samples; HPLC; Hydrophilic ionic liquid; Phenolic compound