Abstract
Ittrich's p-nitrophenol method for oestrogen determination has been examined using a spectrofluorimetric technique. It is concluded that the degree of specificity is considerably higher in spectrofluorimetry than when spectrophotometry is used. Determinations of oestriol in urinary extracts prepared by a comparatively simple fractionating technique have been carried out with satisfactory specificity and precision. By this method amounts of steroid as small as 0.02 μg per 20 ml urine can be estimated.