Gas chromatographic-mass spectrometric analysis of endogenous levels of estradiol in plasma and in cytosol from rat uterus.
A method that permits the analysis of low levels of estradiol in plasma from women, men and rats and in cytosolic fractions of uterine tissue is described. The samples are extracted with Amberlite XAD-2 and a phenolic fraction is isolated on a lipophilic ion exchanger. Less polar contaminants in this fraction are separated from estradiol on Sephadex LH-20. Estradiol from human plasma can then be analysed by gas chromatography-mass spectrometry (GC-MS) as the trimethylsilyl ether using a capillary column and single ion monitoring of m/z 416. Samples from rat plasma and uterine cytosol require final purification by high-performance liquid chromatography prior to the GC-MS analysis. The approximate detection limits with the GC-MS instrument used were 1 x 10(-11)--2 x 10(-11) moles/l in plasma and 5 x 10(-11) moles/kg in the uterus. Problems in the purification procedures and the specificity and sensitivity of GC-MS analyses are discussed.
D000818:Animals; D002467:Cell Nucleus / Q000032:analysis; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D003600:Cytosol / Q000032:analysis*; D004958:Estradiol / Q000097:blood* / Q000302:isolation & purification; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D051381:Rats; D012016:Reference Values; D014599:Uterus / Q000032:analysis*
D004958:Estradiol