Mass spectrometric analysis of 7-oxygenated androst-5-ene structures. Influence in trimethylsilyl derivative formation.
Rapid Commun Mass Spectrom
; 34(17): e8834, 2020 Sep 15.
Article
em En
| MEDLINE
| ID: mdl-32424893
ABSTRACT
Several authors have described the generation of androsta-3,5-diene-7-one structures from androst-5-ene-3,7-dione or androst-5-ene-3ß-ol-7-one under acidic conditions and/or at high temperatures. The goal of this study was to observe and to describe the results obtained after the chromatographic analysis of the trimethylsilyl derivatives of reference materials of 7-oxo-DHEA, 7α-hydroxy-DHEA, 7ß-hydroxy-DHEA, and androsta-3,5-diene-7,17-dione known as arimistane. METHODS:
The purity of the analyte reference materials was verified by liquid chromatography/quadrupole mass spectrometry. The trimethylsilyl derivatives obtained using several mixtures with MSTFA (N-methyl-N-trimethylsilyl trifluoroacetamide) in comparison with solely MSTFA were analyzed by gas chromatography coupled to a time-of-flight detector equipped with a multimode inlet or to a simple quadrupole detector with a split/splitless inlet.RESULTS:
The study showed that the formation of arimistane from 7-oxo-DHEA occurs using common derivatization reagents used for the analyses by gas chromatography (GC). In addition, the formation of the enolized TMS derivative of 7-oxo-DHEA was observed in considerable amount when it was reacted with MSTFA. The analysis of 7α-hydroxy-DHEA resulted in the detection of ~1% of arimistane. The formation of unexpected artifacts from derivatization is influenced by the reagent itself, the reaction temperature, the inlet used and its configuration.CONCLUSIONS:
The derivatization reagent, instrumental conditions (inlet), as well as the chemical structures of the analytes present in the matrix, can influence the results. So, before describing a new feature as a potential "new" metabolite, special caution must be taken since we could actually be dealing with an artifact.
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Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Itália