Use of Porter–Silber and Schiff Reagents as Spot Tests for Steroids applied on Paper and their Application to the Study of Rat Adrenal Lipids

Abstract

THE formation of phenylhydrazones with an absorption maximum at 410 mµ by the method of Porter and Silber characterizes steroids with a dihydroxyacetone side-chain. These authors recently reported that the reaction also occurred with the aldehydes of corticosterone and of 11-dehydrocorti-costerone and that with the latter compounds the phenylhydrazone developed at a more rapid rate¹. The specificity and difference in speed of the reaction are also evident when it is carried out on paper. A bright yellow colour develops when a region containing a minimum of 2 µgm./cm.² of the chromogen is passed through the Porter–Silber reagent (25 ml. water, 41 ml. conc. sulphuric acid, 34 ml. ethyl alcohol and 43 mgm. phenylhydrazine hydrochloride). The colour appears instantly with C-21 aldehydes and their acetates, and in 1–2 hr. with steroids containing the dihydroxyacetone side-chain and their acetates. It is stable for days provided the paper is not rinsed or warmed, and under these conditions the paper does not char. Corticosterone, 17-hydroxyprogesterone and other steroids tested gave no colour at a concentration of 25 µgm./cm.².