The colorimetric estimation of the oestrogenic hormones

Abstract

An improvement of the original method (Biochem. Ztschr. 239, 209. 1931). by using a 2.5% soln. of [beta]-naphthol in conc. H3SO4 as the reagent and by determination of the residual color not due to oestrone for impure urinary extracts. It is essential to adhere to the details given in the original. With the methods of extraction and purification described, it is possible to determine reliably oestrone contents as low as 500 i.u. per liter of urine.