EN
The efficiency of four extraction techniques (shaking extraction, column extraction, accelerated solvent extraction (ASE), and ultrasonic assisted extraction) and two clean-up procedures was evaluated in order to find the best procedure. The ASE proved to be the best extraction method with the highest recovery rales (84%-91%) and imprecision less than 15%. Application of the three- column cleanup procedure delivered slightly better cleanup efficiency in comparison with two-step cleanup but the use of two columns is less time consuming, cost-effective, and enabled to process more samples with the bioassay.