title: [Determination of free and conjugated 16 alpha-hydroxyestrone (16 alpha-OH E1) in serum by mass fragmentography using gas chromatography mass spectrometry].
abstract: A simple, rapid and highly specific method for the determination of maternal and cord serum 16 alpha-hydroxyestrone (16 alpha-OH E1) during pregnancy and at delivery was developed by mass fragmentographic technique using a Gas chromatography--Mass spectrometry (GC-MS) with application of deuterated estradiol as an internal standard. The equipment used was Shimadzu LKB9000 GC-MS (MID-PM). The T.F.A. derivative of the compounds was analyzed using the GC-MS system equipped with a 1 m glass coil, 1% OV-1 on chromosorb w 60 approximately 80 mesh. The flow rate of carrier gas (helium) was 25 ml/min. The temperatures of column oven, separator and ionization source were kept at 190 degrees C, 270 degrees C and 290 degrees C, respectively. The ionization energy and trap current were 70 eV and 60 microA, respectively. The mass spectrum showed molecular ions at m/ e467 and m/ e478 corresponding to the T.F.A. derivatives of d3-E2 and 16 alpha-OH E1 respectively. Evaluation of the method assessed by recovery experiments was 99.2 percent when 10 ng of 16 alpha-OH E1 was added to 1.0 ml of male serum treated with charcoal. The coefficient of variation was 4.2 percent. Serum conjugated 16 alpha-OH E1 levels during pregnancy increased with progressing gestation. The levels in early pregnancy (5th approximately 15th week), middle pregnancy (16th approximately 27th week) and late pregnancy (28th approximately 42th week) were 1.72 +/- 0.43 ng/ml, 5.35 +/- 2.60 ng/ml, 11.92 +/- 3.93 ng/ml (mean +/- S.D.), respectively. Mean levels of 16 alpha-OH E1 in the umbilical artery were 11.61 +/- 5.17 ng/ml which were statistically higher than these in the maternal peripheral vein (6.06 +/- 4.72 ng/ml) and umbilical vein (9.16 +/- 3.77 ng/ml). Serum 16 alpha-OH E1 levels in the samples obtained from anencephalic pregnancy were significantly lower than those in normal pregnancy, suggesting that fetal adrenal function may be involved in the formation of this steroid during pregnancy.
mesh_terms: D002849:Chromatography, Gas; D004958:Estradiol / Q000097:blood; D004970:Estrone / Q000031:analogs & derivatives*; D005260:Female; D005312:Fetal Blood / Q000032:analysis; D005313:Fetal Death / Q000097:blood; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D006894:Hydroxyestrones / Q000097:blood*; D013058:Mass Spectrometry; D011247:Pregnancy
chemical_list: D006894:Hydroxyestrones; C026702:16-hydroxyestrone; D004970:Estrone; D004958:Estradiol