20 -hydroxypregn-4-en-3-one, an Interfering Fluorogen in Assay of Corticosterone

SummaryA comparison of 20α-hydroxypregn-4-en-3-one and corticosterone reveals that their fluorescence properties are similar in concentrated sulphuric acid. Since rodent ovaries secrete 20α-hydroxypregn-4-en-3-one, this steroid may interfere with the assay of corticosterone by fluorimetric techniques; however, interference may be reduced by the use of a petroleum ether wash. It is suggested that a fluorescence method may be used as a sensitive assay for 20α-hydroxypregn-4-en-3-one.