Rapid and simultaneous measurement of estrone, estradiol, estriol and estetrol in serum by high performance liquid chromatography with electrochemical detection

A high performance liquid chromatographic (HPLC) method with electrochemical detection (ECD) was developed for the simultaneous measurement of estrone, estradiol, estriol and estetrol in serum. These hormones were extracted with diethylether, chromatographed on an silica-octadecyl silane (ODS) column with an eluent of phosphate buffer solution-acetonitrile-methanol (volume ratio 152 : 85 : 40), and detected by ECD at + 1.0 V vs. Ag/AgCl. In comparisons between the values measured by this method and radioimmunoassay, significant correlations were noted for estrone (r = 0.759, p < 0.01), estradiol (r = 0.816, p < 0.001) and estriol (r = 0.830, p < 0.001). In clinical applications of this method, differences between cases of the normal and the anencephalic pregnancy in the thirty-eighth week of gestation were distinct not only in the individual estrogen, but also in the profile analysis of estrogens. With this method, all 4 serum estrogens above approximately 500 pg/ml could be measured within 2h, and the method seemed to be clinically applicable.