Indirectly suspended droplet microextraction of water-miscible organic solvents by salting-out effect for the determination of polycyclic aromatic hydrocarbons

A simple and low‐cost method that indirectly suspended droplet microextraction of water‐miscible organic solvents (ISDME) by salting‐out effect before high‐performance liquid chromatography and ultraviolet (HPLC‐UV) detection was used for the determination of polycyclic aromatic hydrocarbons (PAHs) in different samples. The ISDME is a combination of salting‐out extraction of water‐miscible organic solvent and directly suspended droplet microextraction (DSDME). Ninety‐five microliters water‐miscible organic solvent (1‐propanol) was added to a 500‐µL sample. A homogeneous solution was formed immediately. To produce a steady vortex at the top of the solution, the sample was agitated at 700 rpm using a magnetic stirrer. By the addition of ammonium sulfate (saturated solution) to the homogeneous solution, 1‐propanol was separated and collected at the bottom of the steady vortex. Finally, 20 µL 1‐propanol was injected into HPLC‐UV. The effects of important parameters such as water‐miscible organic solvent (type and volume), type of salt, and extraction time were evaluated. Under optimum conditions, the method has a good linear calibration range (0.1 µg/L–300 µg/L), coefficients of determination (R2 > 0.998), low limits of detection (between 0.02 µg/L and 0.27 µg/L), and acceptable recovery (>85.0%). Environ Toxicol Chem 2014;33:2694–2701. © 2014 SETAC