A sensitive method based on ionic liquid dispersive liquid-liquid microextraction(IL-DLLME) and high performance liquid chromatography with diode array detector(HPLC-PDA) was developed for the preconcentration and determination of seven naphthalenediols in environmental water samples.The ionic liquid,1 butyl 3 methylimidazolium hexafluorophosphate([C4MIM][PF6]) was used as extraction agent,and 8.0 mL of aqueous phase was selected.Some important factors affecting the extraction efficiency such as amount of [C4MIM][PF6],pH value of aqueous phase,extraction time and salt concentration were optimized.The optimized conditions were as follows:150 μL[C4MIM][PF6],pH value of aqueous solution:5.0-7.0,vortex extraction time:3 min, sodium chloride:0.20 g/mL.Under the optimized conditions,the calibration curves of 7 naphthalenediols were linear in the certain concentration range with correlation coefficients not less than 0.997 7.The enrichment factor of this method was 57,and the detection limits of this method(S/N=3) were between 0.3 μg/L and 1.0 μg/L.The average recoveries of naphthalenediols at three spiked levels in negative environmental water sample ranged from 83.5% to 103% with relative standard deviations(RSD,n=6) of 1.1%-3.8%.The developed method is rapid,sensitive and environment friendly,and is suitable for the detection of trace naphthalenediols in environmental water samples. |