Photocontrol of anionic micelles containing lipophilic crowned spirobenzopyran

In order to apply micelles to novel type of separation and analytical chemistry, a crowned spirobenzopyran derivative, which is a spirobenzopyran derivative bearing a crown ether moiety as the hydrophilic part and a long alkyl chain as the lipophilic moiety, was solubilized in aqueous micelle solutions consisting of an anionic surfactant. Structural changes of the micelle based on the photochromic isomerization of crowned spirobenzopyran were studied by fluorescence spectra and a light scattering method. It was found that the critical micelle concentration (cmc) was changed appreciably by photoirradiation, while the particle size and the aggregation number of surfactant were slightly changed.