Tunable solid-state fluorescent materials self-assembled by a cationic dye acridine orange and an anionic biosurfactant sodium deoxycholate

Abstract

Tunable solid-state fluorescence of a cationic dye acridine orange (AO) aggregates were triggered by introducing an anionic biosurfactant sodium deoxycholate (NaDC) as matrix. The NaDC/AO assembles with morphology of flabellate and dumbbell-shaped fiber bundles were formed via ionic self-assembly (ISA) strategy and both the ratio of NaDC to AO and temperature have influence on the morphology. Composition and driving force analysis of the microfibers have been investigated. The results revealed that the interaction between NaDC and AO was strongly influenced by direct electrostatic forces between the COO groups in NaDC and N+ in AO, respectively. Besides the electrostatic interactions, which proved to be the main driving forces for the formation of the supramolecular aggregates, the π-π stacking and hydrogen bond interactions also makes some contribution. What’s more, the fluorescence have dramatically enhanced upon the formation of complex, and the wavelength and intensity of this solid-state aggregates fluorescence can be further controlled by the molar ratio of NaDC to AO which induced the fluorescence lifetime and fluorescence quantum yield both increase with the increased concentration of NaDC. Thus, it is expected that the facile design of tunable solid-state fluorescence material by the ISA strategy could be used to provide new insight for the development of solid luminescent materials.