Preparation and Characterisation of Self-Assembled Dye Fibers

Abstract

Two types of fibers have been prepared by self-assembly. The first system is made of Astrophloxine hydrogel fibers, based on the stacking of molecules by π- π interactions. Various properties of the hydrogel have been characterized with UV-vis absorbance, Fluorescence spectroscopy, calorimetric profiles, and rheology. The hydrogel shows temperature-dependent fluorescence. Above the melting temperature T>44°C, fluorescence and hydrogel structure are lost, but they are recovered upon cooling, demonstrating that the process is reversible. The fibers also showed a temperature-dependent birefringency. The second system of fibers was formed by ionic self-assembly (ISA) of two oppositely charged dyes. This system was characterized by SEM and TEM, as well as X-Ray diffraction. The ISA fibers were able to encapsulate a drug, showing promise for controlled drug release