The reaction of cationic dyes with disodium cromoglycate

The reaction of disodium cromoglycale with five cationic dyes: crystal violet, Janus green, methylene blue, methyl green, and safranine, was investigated. Spectroscopic shifts indicated that at low concentration (0.01 mM) all these dyes were able to form complexes (ion paris) with the cromoglycale anion. In addition, the complexes formed by crystal violet and Janus green were extractable into chloroform.