Document Detail


Unique potentiometric detection systems for HPLC determination of some steroids in human urine.
MedLine Citation:
PMID:  19156641     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Isocratic HPLC with potentiometric detection is used for the determination of some 17-ketosteroids (17-KS), e.g., androsterone, dehydroepiandrosterone and estrone, and their respective sulfated conjugates (17-KSS). Glassy carbon or composite electrodes containing a mixture of graphite and poly(vinyl chloride), PVC, were used as substrate electrodes. These substrates were covered either by montmorillonite or potassium tetrakis(p-chlorophenyl) borate containing PVC-based rubber phase membranes. The neutral 17-KS compounds were derivatized with Girard's reagent P (GP) to obtain cationic pyridinium acetohydrazones prior to the HPLC/potentiometric detection assay. No side reactions were observed, and the GP itself was not interfering. The method yielded accurate and reproducible results and was applicable to samples containing down to micromolar concentrations. Next, the 17-KSS compounds, acting as anionic charged molecules, were determined directly in human urine samples with the HPLC/potentiometry combination without preliminary derivatization. For this purpose, a new anion-sensitive potentiometric electrode was developed using a macrocyclic polyamine containing, PVC-based, rubber phase membrane. The three 17-KSS compounds were also determined accurately down to micromolar concentrations. Especially, the main androgen metabolites as dehydroepiandrosterone sulfate and androsterone sulfate could be selectively determined with a developed potentiometric sensor in human urine samples without time-consuming cleanup and preconcentration step.
Authors:
Bert Vissers; Joseph Everaert; Justyna Sekula; Anna Malak; Hugo Bohets; Grzegorz Bazylak; Luc J Nagels
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of separation science     Volume:  32     ISSN:  1615-9314     ISO Abbreviation:  J Sep Sci     Publication Date:  2009 Jan 
Date Detail:
Created Date:  2009-02-02     Completed Date:  2009-04-20     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101088554     Medline TA:  J Sep Sci     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  167-79     Citation Subset:  IM    
Affiliation:
Departement Chemie, Faculteit Wetenschappen, Universiteit Antwerpen, Antwerpen, Belgium.
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MeSH Terms
Descriptor/Qualifier:
17-Ketosteroids / chemistry*,  urine*
Betaine / analogs & derivatives
Calibration
Chromatography, High Pressure Liquid / methods*
Electrodes
Humans
Molecular Structure
Pilot Projects
Potentiometry / methods*
Sulfur / chemistry
Chemical
Reg. No./Substance:
0/17-Ketosteroids; 107-43-7/Betaine; 123-46-6/Girard's reagent T; 7704-34-9/Sulfur

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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