A New Technique for studying the Quantitative Aspects of Cytochemical Reactions and its Application to the Feulgen Reaction

Abstract

QUANTITATIVE microspectrophotometry of cytochemically stained substances in cellular structures should be based on a knowledge of the stoichiometry of the reactions involved and the conditions influencing it. Thus far independent chemical analysis of individual cellular structures to study the quantitative relation between colour and amount of stained substance in general is not possible. This relation can be studied on a macro-scale by incorporating the substance in a kind of artificial section or model system which makes it possible to carry out the staining procedure under cytochemical conditions. For this purpose thin cellulose films were chosen. The extinction of the film after the staining procedure is proportional to the mass of the stained substance per unit area in the film. This mass is proportional to the amount of cellulose in the same area, provided the substance is uniformly distributed.