The Mechanism of Staining Explained on A Chemical Basis. I. The Reaction Between Dyes, Proteins and Nucleic Acid

Abstract

Basic dyes cause an increase in hydrogen-ion concentration when added to a solution containing nucleic acid, the both solutions were originally at the same pH. Acid dyes have no effect on nucleic acid solutions. Basic dyes show the same behavior when treated with solutions of typical proteins. Acid dyes when treated with proteins show an analogous effect but in the opposite direction. The only adequate explanation found is that there is a definite reaction between the dye ions and the oppositely charged ions of protein or nucleic acid. The bearing of these results on the theory of staining is discussed. The growing recognition of the dominance of chemical forces in colloidal adsorption behavior is indicated, and certain of the experimental bases for this recognition are pointed out and discussed.