Temperature-controlled ionic liquid dispersive liquid-phase microextraction for the sensitive determination of triclosan and triclocarban in environmental water samples prior to HPLC-ESI-MS/MS

A novel dispersive liquid-phase microextraction method without dispersive solvents has been developed for the enrichment and sensitive determination of triclosan and triclocarban in environmental water samples prior to HPLC-ESI-MS/MS. This method used only green solvent 1-hexyl-3-methylimidazolium hexafluorophosphate as extraction solvent and overcame the demerits of the use of toxic solvents and the instability of the suspending drop in single drop liquid-phase microextraction. Important factors that may influence the enrichment efficiencies, such as volume of ionic liquid, pH of solutions, extraction time, centrifuging time and temperature, were systematically investigated and optimized. Under optimum conditions, linearity of the method was observed in the range of 0.1-20 mu g/L for triclocarban and 0.5-100 mu g/L for triclosan, respectively, with adequate correlation coefficients (R>0.9990). The proposed method has been found to have excellent detection sensitivity with LODs of 0.04 and 0.3 mu g/L, and precisions of 4.7 and 6.0% (RSDs, n = 5) for tridocarban and triclosan, respectively. This method has been successfully applied to analyze real water samples and satisfactory results were achieved.