Room temperature phosphorescence study on supramolecular system of cyclodextrin/surfactants

摘要

THE microenvironmental properties of cyclodextrin/surfactants supramolecular system have been investigated with a variety of methods. Usually, a 1:1 stoichiometry of cyclodex-trin/surfactant and noneffectiveness of cyclodextrin on the micellization behavior are reported in most cases. But, β-cyclodextrin (β-CD)-induced aggregation of the surfactants below CMC has been recently assumed to take place in the cyclodextrin/surfactant mixed system. Although the room temperature phosphorescence (RTP) emission can be only observed under the condition of deaerated solution and (or) rigid supports in most cases, recently, the RTP emission in aerated solution has been observed based on the relatively rigid inner cavity of cyclodex-trins. The RTP enhancementis related to the formation of rigid inclusion complex and its effectiveness in shielding photoexcited lumophores from oxygen. In the present note, the intense RTP of a-bromonaphthalene(α-BrN) in fi-CD solution induced by surfactants has been observed.The properties of supramolecular system of cyclodextrin/surfactant and aggregation of surfactant in the presence of β-CD are investigated by using RTP spectra of α-BrN as a probe.