On the fluorimetric determination of oestriol in pregnancy urines after thin layer chromatography.

An improved method is described for the determination of oestriol concentrations in urines of pregnant women. Oestriol is detected as a derivate of 1-dimethylaminonaphtalene-5-sulphonylchloride (DANSYLchloride). The method has the following characteristics: 1. The recovery of oestriol-16-glucuronide is 94%. 2. For the interpretation of the results obtained with this method mean values and 95% probability bounds of urinary oestriol excretion for each week of the last three months of pregnancy are given. (e.g. 49--125 mumol/24 h at 32 weeks of gestation, 108--238 mumol/24 h at 40 weeks). 3. The coefficient of variation of the method is 4% (from day to day). 4. The lowest detectable concentration is 3 mumol/l. 5. Influence of glucose can be eliminated. 6. Other urinary compounds have no influence on the determination.