Excimer Formation of a Water-Soluble Fluorescence Probe in Anionic Micelles and Nonionic Polymer Aggregates

摘要

The excimer/monomer emission of the water-soluble fluorescence probe, sodium pyrene-3-sulfonate (Py-S), has been investigated in aqueous solutions containing anionic micelles of sodium dodecyl sulfate (SDS), nonionic micelles of a series of polyethylene glycol n-nonyl phenyl ethers (C9PhEn) and aggregates of poly(ethylene oxide-propylene oxide-ethylene oxide) copolymers (EPE). The influences of temperature, pressure, and added salt on the intensity of the excimer to monomer emission (Ie/Im) in the various systems were investigated. Dramatic differences were observed in the intensity of the excimer to monomer emission (Ie/Im) under the varying environmental conditions. The results are interpreted in terms of a dynamic equilibrium of Py-S between the aqueous phase and the aggregate phases in response to variations of aggregate structure that are induced by the experimental variations.