New polymeric mixed-micelle electrokinetic system for simultaneous determination of nine endogenous steroids in human urine

CONTIN M.; FLOR SABRINA; MANUELA MARTINEFSKI; PUZZIO CARLA; LUCANGIOLI S.; TRIPODI V.

FLORIANOPOLIS

Simposio; 16th Latin American Symposium on Biotechnology, Biomedical, Biopharmaceutical and Industrial Applications of Capillary Electrophoresis and Microchip Technology; 2010

LACE

Steroid hormones are an important class of compounds with diverse biochemical and physiological functions and their quantitation is important in the assessment of the state of human health. A great interest exists in the development of rapid and reliable methods for detection and/or determination of steroids in several matrices in different areas such as biomedical applications (metabolic disorders, pregnancy, cancer and bone diseases), pharmaceuticals quality control and doping control of hormonal drugs. A new capillary electrophoresis system based on the use of polymeric-mixed micelles (cholic acid, SDS and the poloxamine Tetronic â 1107), was developed for the simultaneous determination of nine steroids in human urine. This method allows the baseline separation and quantitation of cortisol, androstenedione, estriol, dehydroepiandrosterone sulfate, testosterone, dehydroepiandrosterone, estrone, progesterone and estradiol in less than 25 minutes showing to be sensitive enough to detect low concentrations of these steroids in urine samples (5-45 ng/mL). The optimized electrophoretic conditions was performed using a 50 cm x 75 µm capillary, 18 kV, 25 ºC, with 44 mM CA, 10 mM SDS, 0.05% w/v tetronic Ò 1107, 2.5% v/v methanol, 2.5% v/v tetrahidrofuran in 5 mM borate- 5 mM phosphate buffer (pH=8.0) as a background electrolyte and a dual 210/254 UV-detection. The method can simultaneously determine 0.1-120µg/mL which corresponds to 5-6000 ng/mL of steroids in 2 mL urine. The recoveries ranged between 82.4 and 101.5%. Due to its simplicity, speed, accuracy and reliability, the proposed method could be a potential alternative to the traditional methodologies used with clinical purposes.