Universität zu Köln

Piper, Thomas ORCID: 0000-0002-7462-6693, Geyer, Hans and Schaenzer, Wilhelm (2010). Degradation of urine samples and its influence on the C-13/C-12 ratios of excreted steroids. Drug Test. Anal., 2 (11-12). S. 620 - 630. HOBOKEN: WILEY. ISSN 1942-7611

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Abstract

The degradation processes in deficiently stored urine samples are well investigated regarding steroid concentrations and diagnostic ratios, such as the quotient of testosterone divided by epitestosterone. In contrast, nothing is known about the influence on carbon isotope ratios (CIR) by inappropriate storage conditions. In general, it is assumed that degradation, i.e. deconjugation or dehydrogenation, does not change CIR and thus CIR can be used in cases where the steroid profile turns out to be invalid. Therefore, the CIR of urinary steroids was investigated in different urine samples during the course of degradation over a time period of six months. Several steroids excreted as glucuronides (androsterone (A), etiocholanolone (E), testosterone, pregnanediol (PD) and 5 alpha- and 5 beta-androstane-3 alpha,17 beta-diol) or sulfo-conjugated (A, E and androst-5-ene-3 beta,17 beta-diol (5EN17b)) were investigated together with their unconjugated correspondents (A, E, PD and 5EN17b) and the main dehydrogenation products (5a- and 5 beta-androstane-3,17-diol and androst-4-ene-3,17-diol). For this purpose, the exiting methods for CIR determination were extended and validated. In addition, the urinary concentrations of all investigated steroids were monitored. Particular attention was paid to dehydroepiandrosterone conjugated and unconjugated together with its degradation product 3 alpha,5-cyclo-5 alpha-androstan-6 beta-ol-17-one as here the strongest influence on CIR was expected. Copyright (C) 2010 John Wiley & Sons, Ltd.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Piper, Thomas UNSPECIFIED orcid.org/0000-0002-7462-6693 UNSPECIFIED Geyer, Hans UNSPECIFIED UNSPECIFIED UNSPECIFIED Schaenzer, Wilhelm UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-493174
DOI:	10.1002/dta.219
Journal or Publication Title:	Drug Test. Anal.
Volume:	2
Number:	11-12
Page Range:	S. 620 - 630
Date:	2010
Publisher:	WILEY
Place of Publication:	HOBOKEN
ISSN:	1942-7611
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language MASS-SPECTROMETRIC ANALYSIS; DOPING CONTROL; CARBON; EPITESTOSTERONE; FRACTIONATION; HYDROLYSIS; SOLVOLYSIS; CLEAVAGE; SULFATE; PROFILE Multiple languages Biochemical Research Methods; Chemistry, Analytical; Pharmacology & Pharmacy Multiple languages
URI:	http://kups.ub.uni-koeln.de/id/eprint/49317