A simple, fast, cheap, and effective method named deep eutectic solvent based on emulsification liquid-liquid microextraction (DES-ELLME) was employed to extract thiophenols from water samples. DES was specified by Fourier transform-infrared (FT-IR) spectroscopy, CHN elemental analysis, proton and carbon nuclear magnetic resonance (1H-NMR and 13C-NMR). 50 µL DES was added to aqueous sample solution and a uniform solution was made immediately. After injection of 50 µL acetone into the solution a turbid state was provided. Then, phase separation (DES rich phase/aqueous phase) was done by centrifugation. DES rich phase was submitted to gas chromatograph with a flame ionization detector (GC-FID). Effective factors, including the volume of acetone and DES, ultrasonic time, and pH were combined using a desirability function (DF) and optimized through a Box-Behnken design. Calibration graphs were linear in concentration range 0.02-100 mg/L under optimum experimental circumstances; coefficients of correlation were more than 0.999. The limits of detection and quantification were in the ranges of 10-15 μg/L and 33-50 μg/L, respectively. This method was used to determine target analytes in spiked water samples; the relative mean recoveries were 96 to 104%.
