Solidified floating organic drop microextraction combined with high performance liquid chromatography for the determination of carbamazepine in human plasma and urine samples.

Solidified floating organic drop microextraction (SFODME) in combination with high performance liquid chromatography was used for separation/preconcentration and determination of carbamazepine (CBZ) in human plasma and urine samples. Parameters that affect the extraction efficiency such as the type and volume of extraction solvent, ionic strength, sodium hydroxide concentration, stirring rate, sample volume and extraction time, were investigated and optimized. Under the optimum conditions (extraction solvent, 40 µL of 1-undecanol; sodium hydroxide concentration, 1 mol/L; temperature, 50 °C; stirring speed, 400 r/min; sample volume, 8 mL; sodium chloride concentration, 3% (w/v) and extraction time, 60 min) the calibration curve was found to be linear in the mass concentration range of 0.4-700.0 µg/L. The limit of detection (LOD) was 0. 1 µg/L and the relative standard deviation (RSD) for six replicate extraction and determination of carbamazepine at 100 µg/L level was found to be 4.1%. The method was successfully applied to the determination of CBZ in human plasma and urine samples.