Abstract
Measurement of Estriol (E~3~) and estradiol (E~2~) within 22 min by highβperformance liquid chromatography (HPLC) was achieved in this study, and the values were compared with those of a radioimmunoassay (RIA). A totally computerized HPLC method was developed for measuring unconjugated E~3~(uβE~3~) and E~2~ (uβE~2~) in the sera of pregnant women. The serum samples were injected directly into the apparatus and transferred to a preβtreatment column where the estrogens were absorbed while hydrophilic components such as proteins and carbohydrates were excluded. The estrogens were then passed through another separation column containing a new type of polymer gel. The mobile phase consisted of an acetonitrileβwater mixture, and separation was achieved by means of a reversedβphase procedure. The eluate was monitored for fluorescence. All procedures were monitored and controlled with a builtβin microcomputer. Serum samples from 97 normal pregnant women at 20β41 wk gestation were simultaneously assayed by HPLC and RIA. The correlations obtained by HPLC and RIA were as follows: uβE~3~ y = 0.905xβ0.385, with a coefficient of correlation of r = 0.912; for uβE~2~, y = 0.964x + 5.024, with a coefficient of correlation of r = 0.841 (y, RIA value; x, HPLC value). The quick measurement of uβE~3~ and uβE~2~ by HPLC can be a useful method for evaluating fetoplacental function.