1961 年 81 巻 7 号 p. 1036-1039
17α-Ethynylestradiol, when heated with Iron-Kober test solution for 3 minutes, shows maximum absorption at 560mμ, differing from other estrogens such as estrone and 17β-estradiol. In addition, estrone and 17β-estradiol do not absorb at 560mμ so that they can be detected easily even if present. This coloration reaction can be utilized for colorimetric determination since the absorbancy and amount of 17α-ethynylestradiol are in linear relationship in the range of 10-40γ of 17α-ethynyl-estradiol. There is no significant difference in the determined value even in the presence of 50γ of estrone.
The procedure is carried out exactly the same as with Iron-Kober T. S. reagent A, used for coloration reaction of 17β-estradiol. Optimal conditions for colorimetric determination of 17α-ethynylestradiol were examined, since there has been no appropriate method of determination for this compound, by varying heating time and period of standing. It was thereby found that this is a practicable method of analysis.