A simplified vortex-assisted emulsification microextraction method for determining personal care products in environmental water samples by ultra-high-performance liquid chromatography†
Abstract
A vortex-assisted emulsification microextraction (VAEME) procedure has been evaluated for the determination of ten personal care products (PCPs), including seven preservatives (parabens), two UV filters (benzophenones), and one disinfectant (triclosan), in environmental waters. The method is utilized in combination with ultra-high performance liquid chromatography (UHPLC) and UV detection. The results obtained from the liquid-phase microextraction method are reasonably simple because the method only needs one extractant (200 μL of trichloromethane under optimum conditions) and it completely avoids the use of any dispersive solvent or surfactants to help the emulsification. The optimized method ensures the correct emulsification by simple application of 3 min of vortex to 8 mL of aqueous sample at pH 5 containing 15% (w/v) of sodium chloride, followed by centrifugation (5 min at 3500 rpm), droplet sampling using a syringe, droplet solvent evaporation, and reconstitution with 100 μL of a mixture of acetonitrile–water (35 : 65, v/v) before UHPLC injection. The overall extraction time is roughly 10 min, and the chromatographic time ∼12 min. The optimized method was validated and presented average relative recoveries of 112%, average real extraction efficiencies of 82.7%, inter-day precision values with relative standard deviation (RSD, in %, for n = 9) values lower than 10%, and enrichment factors between ∼20 and ∼100, for a spiked level of 3.75 μg L−1. Limits of detection down to 0.03 μg L−1 were also obtained. The method performed well for environmental water samples with different natures and complexities.