Induced Chiral Chromonics Confined in Micrometric Droplets

Chirality emergence in biological systems is common but the chiral expression from the molecular to macroscopic level in water-based systems is poorly understood. Among water-based systems, chromonic liquid crystals have recently received a lot of attention due to the spontaneous chirality they show when confined in curved geometries. Confinement of chiral-induced chromonics is not trivial since they are three component systems whose time stability is a delicate thermodynamic balance. In this work, a well-defined periodic Frank-Pryce texture, typical of chiral thermotropic liquid crystals, is observed in microspheres of a chiral induced chromonic embedded in a poly(dimethylsiloxane) matrix. This texture slowly degrades in time and a possible mechanism behind the degradation process is suggested via X-ray diffraction and atomic force microscopy measurements on thin chromonic films. To stabilize this texture and to control the structure periodicity, cations are added to the three components system in an attempt to tune the non-covalent interactions between molecules and supramolecular stacks. The study of the effects of this addition allows for better insight into the molecular interactions that occur in the chiral induced mesophase. This is a crucial point in view of possible biocompatible technological applications.