Probing Chemical Environment Using Polymeric Reverse Micellar Solutions Which Sequester Inorganic Coordination Complex Fluorophores

Abstract

A series of tris(bipyridine)ruthenium(II) chloride ([Ru(bpy)3]Cl2)-sequestered reverse micellar solutions of variable surfactant concentration were examined using fluorescence spectroscopy before and after thermal radical polymerization of the nonpolar phase. The [Ru(bpy)3]Cl2 emission spectra simulated aqueous solution chemical environments irrespective whether the nonpolar phase is liquid or polymerized into a solid. A range of surfactant concentrations were examined. Emission maxima of the reverse micelle solution-sequestered [Ru(bpy)3]Cl2 species are red-shifted with respect to aqueous [Ru(bpy)3]Cl2. The red-shift can be interpreted in the context of increasing chemical environment polarity. Emission maxima of the [Ru(bpy)3]Cl2 species of polymerized nonpolar phase at approximately 600 nm were consistent with [Ru(bpy)3]Cl2 aqueous species. The work represents a pathway to preserve solution-dependent chemical processes of molecular sensors.