Ultrasound- assisted emulsification microextraction for separation of trace amounts of antimony prior to FAAS determination

We describe a simple and rapid method for the ultrasound-assisted microextraction of antimony using the solidified floating organic drop method. The effects of pH, type and volume of the extractant, time of sonication, amount of chelating agent, type and amount of surfactant were investigated and optimized. Bromopyrogollol red is acting as the chelating agent. Antimony(III) ion was extracted into finely dispersed droplets of undecanol after ion-pair formation with the water soluble chelator and the cationic detergent benzyldimethyltetradecylammonium chloride. Flame atomic absorption spectrometry was used for the detection. The resulting calibration is linear in the concentration range from 4.0 to 900?ng?mL^-1 of Sb(III) with a correlation coefficient of 0.9981. The enrichment factor is 67, the detection limit is 0.62?ng?mL^-1, and the relative standard deviation is?±?3.6% (at 100?ng?mL^-1; for n?=?10). The method was successfully applied to the determination of antimony in water samples.