Simultaneous measurement of serum testosterone and dihydrotestosterone by liquid chromatography-tandem mass spectrometry.
Clin Chem
; 54(11): 1855-63, 2008 Nov.
Article
em En
| MEDLINE
| ID: mdl-18801940
ABSTRACT
BACKGROUND:
Recent reports have described inherent problems with androgen immunoassays compared with mass spectrometry analyses.METHODS:
We developed a method for measuring serum testosterone (T) and 5alpha-dihydrotestosterone (DHT) simultaneously via liquid-liquid extraction followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with positive-mode electrospray ionization.RESULTS:
The DHT and T calibrators showed a linear response from 0.069 nmol/L to 34.4 nmol/L and 69.3 nmol/L, respectively. T interference in the DHT assay and vice versa were negligible. Within- and between-run imprecision values were <5% for both analytes. Percent recoveries of T and DHT spiked into samples at concentrations spanning the calibration curve were 100%-113% and 98%-107%, respectively. The lower limit of quantification was 0.069 nmol/L for both steroids. Serum T concentrations measured by LC-MS/MS were different from those obtained by RIA, especially at lower T concentrations. Serum DHT concentrations measured by LC-MS/MS were markedly lower than those generated by RIA because of the nonselectivity of the RIA without chromatography. The reference intervals (mean +/- 2 SDs) determined for T and DHT were 9.2-33.7 nmol/L and 0.47-2.65 nmol/L, respectively, for 113 healthy adult men and 0.33-2.02 nmol/L and 0.09-0.91 nmol/L, respectively, for 133 healthy premenopausal women.CONCLUSIONS:
We have developed and validated a selective and precise method for simultaneous measurements of serum T and DHT that can be adopted for routine measurements of these androgens in health and disease in men and women.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Di-Hidrotestosterona
/
Testosterona
/
Cromatografia Líquida
/
Espectrometria de Massas em Tandem
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Clin Chem
Assunto da revista:
QUIMICA CLINICA
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Estados Unidos