Improving the Technic of the Feulgen Stain

Abstract

A study has been made of the Feulgen stain, in which the staining fluid is a decolorized basic fuchsin. Particular attention has been given to the variation in behavior of different fuchsin samples, the reagent to be employed in decolorizing the dye, the acidity of solutions, and the value of several counter-stains. A modified procedure is suggested, the details of which are given in the paper. The principle modifications of earlier procedures which are recommended are as follows: the use of a specially purified pararosanilin as a dye; the employment of K2S2O5 instead of NaHSO3 as a decolorizing agent; and counterstaining with fast green in the case of plant tissue or with orange G for animal material.