Stimuli-responsive Self-assembly of Liquid Crystal Droplets via DNA hybridization

Abstract

Self-assembly is a promising method to spontaneously form highly ordered structures or patterns from simple building elements. However, it is challenging to precisely control the assembly process, and the resulting structure is constrained by the inherent properties of the materials used (1). In this work, we propose a design for stimuli-responsive self-assembly of liquid crystal (LC) droplets through DNA hybridization. LC droplets exhibit director configuration transitions in response to external stimuli (2). Single-stranded DNA (ssDNA) has been widely used to direct the self-assembly of building elements such as hard or soft colloids (3). LC droplets act as stimuli-responsive building blocks, and the DNA hybridization of two complementary ssDNA provides a linkage enabling specific interactions among LC droplets. We demonstrate that the interaction among ssDNA-functionalized LC droplets is controlled in a desired direction (Fig. 1a), and the structure of the self-assembled LC droplets is tunable through the reconfiguration triggered by external stimuli (Fig. 1b). We expect that our self-assembly approach will facilitate creating hierarchical and tailorable structures, suitable for soft and smart photonic materials. Moreover, because ssDNA selectively binds to a specific target molecule (e.g., heavy metal ion) with high affinity, ssDNA-functionalized LC droplets allow us to design a highly selective detection system.