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J Chromatogr A

Title:		Extraction of testosterone and epitestosterone in human urine using aqueous two-phase systems of ionic liquid and salt
Author(s):		He C; Li S; Liu H; Li K; Liu F;
Address:		"The Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, College of Chemistry, Peking University, Chengfu Road, Beijing 100871, China"
Journal Title:		J Chromatogr A
Year:		2005
Volume:		1082
Issue:		2
Page Number:		143 - 149
DOI:		10.1016/j.chroma.2005.05.065
ISSN/ISBN:		0021-9673 (Print) 0021-9673 (Linking)
Abstract:		"Based on aqueous two-phase systems (ATPS) consisting of 1-butyl-3-methylimidazolium chloride, a hydrophilic ionic liquid (IL), and K2HPO4, a new and simple extraction technique, coupled with a reversed-phase high performance liquid chromatography (RP-HPLC), was developed for the simultaneous concentration and analysis of testosterone (T) and epitestosterone (ET) in human urine. Under the optimal conditions, the extraction efficiencies for both analytes were 80-90% in a one-step extraction. The method required only 3.0 mL of urine and a single hydrolysis/deproteinization/extraction step followed by direct injection of the IL-rich upper phase into HPLC system for analysis. The method has been satisfactorily applied to the analysis of T and ET in human urine with detection limits of 1 ng/mL and linear ranges of 10-500 ng/mL for both compounds. Compared with conventional liquid-liquid extraction or solid phase extraction, this new method is much 'greener' due to no use of volatile organic solvent and low consumption of IL. The proposed extraction technique opens up new possibilities in the separation of other drugs"
Keywords:		"Chemical Fractionation/methods Chromatography, High Pressure Liquid/methods Epitestosterone/isolation & purification/*urine Humans Imidazoles Temperature Testosterone/isolation & purification/*urine;"
Notes:		"MedlineHe, Chiyang Li, Shehong Liu, Huwei Li, Kean Liu, Feng eng Research Support, Non-U.S. Gov't Validation Study Netherlands 2005/07/23 J Chromatogr A. 2005 Aug 5; 1082(2):143-9. doi: 10.1016/j.chroma.2005.05.065"