Sensitive routine liquid chromatography-tandem mass spectrometry method for serum estradiol and estrone without derivatization.
Anal Bioanal Chem
; 405(26): 8569-77, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-23892882
ABSTRACT
The need for a routinely applicable assay to measure low estradiol levels in adult men, postmenopausal women, and young adolescents was recently discussed in an Endocrine Society position statement. Our aim was to develop a sensitive liquid chromatography-tandem mass spectrometry method for estradiol and estrone in human serum without the need for derivatization or extended extraction protocols. After protein precipitation of serum with a mixture of methanol/acetonitrile (85/15) (v/v) containing isotopic internal standards (17ß-estradiol-16,16,17-d 3 and estrone-2,3,4-(13)C), we quantified estradiol and estrone by two-dimensional liquid chromatography-tandem mass spectrometry with electrospray ionization in the negative mode monitoring 5 × 271.20â145.00 (17ß-estradiol) and 269.20â145.00 (estrone). Sensitivity was increased by using fluoride and summation of 5 identical transitions for estradiol. Our method was analytically validated, compared against direct immunoassays using serum of 25 adult men, and clinically tested by measuring samples of 3 men at baseline and after chemical castration, 30 postmenopausal women and 15 patients receiving aromatase inhibitors. Total imprecision was below 20% for the low quality controls. Limit of quantification was 1.3 ng/L (4.8 pmol/L) for estradiol and 1.2 ng/L (4.4 pmol/L) for estrone. Estradiol in Certified Reference Material BCR-576 was within specified uncertainty limits. No significant ion suppression or interference was observed. Our method showed modest correlation with direct immunoassay for estradiol (r(2) = 0.64) but no correlation for estrone (r(2) = 0.12). Patient sample results were within expected ranges. In conclusion, we developed a routinely applicable liquid chromatography-tandem mass spectrometry method for estradiol and estrone measurement which is sensitive enough for use in men, postmenopausal women, and young adolescents.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cromatografia Líquida
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Estradiol
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Estrona
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Espectrometria de Massas em Tandem
Tipo de estudo:
Diagnostic_studies
/
Guideline
Limite:
Adult
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Aged
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Aged80
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article