Dispersive liquid-liquid microextraction based on solidification of floating organic drop - Determination of non-steroidal anti-inflammatory drugs in waters

Dispersive liquid–liquid microextraction based on solidification of floating organic drop method is a highly efficient method optimized for the first time in the determination of trace levels of ibuprofen, naproxen, diclofenac, and ketoprofen in water samples. Several important parameters affecting the dispersive liquid–liquid microextraction based on solidification of floating organic drop (extraction solvent, ionic strength, pH, dispersion solvent, vortex, and centrifugation times) were studied and optimized using a univariate optimization strategy. High-performance liquid chromatography coupled with a photo-diode array detector was used after the sample preparation. Limits of detection and quantification were in the range of 0.15–0.32 and 0.48–0.98 μg/L, respectively. Moreover, the linear dynamic range was up to 1000 μg/L and determination coefficient was higher than 0.9949. Recoveries in all water samples at two spiking levels (20 and 50 μg/L) were between 80.5 and 102.8% for all the pharmaceuticals. The intra- and interday (n = 5) precision were below 9.4%. Using dispersive liquid–liquid microextraction based on solidification of floating organic drop as a method for the extraction of pharmaceuticals from the aquatic environment is simple, rapid, environmentally friendly, and opens a new door for applications in this field where preconcentration is almost always required