The acridine dyes: their purification, physicochemical, and cytochemical properties. I. A purity test of some commercial acriflavine samples and the identification of their components.

The present investigation was designed to allow a critical comparison of the dye purity of six commercial acriflavine samples. Thin layer chromatography, absorption-, IR- and NMR-spectroscopy were applied for the identification of dye components and impurities. Ambiguities regarding the purity of the acriflavine samples have been resolved, showing that: (a) The finding permits the conclusion, that all analyzed samples of the fluorochrome "acriflavine" are characterized by a two-component dye pattern (acriflavine II and proflavine III), and contain fluorescent impurities. (b) The dye component III was the main component of only one dye sample. The effectiveness of these experiments is concerned with making automated microfluorometric measurement of cells stained with pure dye fractions more quantitative and reproduceable.