A FLUORESCENCE STUDY OF LUMICHROME PHOTOTAUTOMERISM IN DODECYLAMMONIUM PROPIONATE REVERSED MICELLES

Spectral and time-resolved polarized fluorescence experiments were car ried out on N(3)-undecyllumichrome and N(3)-undecyllumiflavin encapsul ated in reversed micelles of dodecylammonium propionate in cyclohexane . The compounds were equipped with a long chain to anchor them to the interphase boundary between the water droplet and the organic phase. T he spectral experiments revealed that the amphiphilic compounds were l ocated at the interphase. The observation that the propionate counter- ion of the micellar ammonium head group enables phototautomerism to yi eld isoalloxazinic fluorescence provided evidence for the close contac t of lumichrome with propionate. Dynamic information was obtained from a two-dimensional maximum entropy method of analysis of the time-reso lved fluorescence data of flavin and phototautomeric lumichrome. On th e basis of these results it was clear that the fluorophores were distr ibuted differently within the micellar boundary region.