Dispersive liquid-liquid microextraction followed by high-performance liquid chromatography as an efficient and sensitive technique for determination of nandrolone and testosterone in human urine

Abstract Dispersive liquid-liquid microextraction (DLLME) and high performance liquid chromatography – UV detection was presented for extraction determination of nandrolone testosterone in human urines. Chloroform at microliter volume level acetonitrile were used as dispersive solvents, respectively. The main advantages method are speed, enrichment factor, recovery, good repeatability solvent µL level. influence several variables (e.g. type disperser ionic strength, etc.) on the sample preparation step carefully evaluated. Under optimum conditions, calibration graphs linear range 5–500 μg L −1 with limit 2.5 both them. relative standard deviation (R.S.D.s) five replicate measurements 9.4% 8.8%, recoveries urine spiking 25.0 ranged between 86.4% 98%. DLLME combined HPLC-UV is a fast, simple efficient