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Designing simple, sensitive, fast, and inexpensive readout devices to detect biological molecules and biomarkers is crucial for early diagnosis and treatments. Here, we have studied the interaction of the chiral liquid crystal (CLC) and biomolecules at the liquid crystal (LC)-droplet interface. CLC droplets with high and low chirality were prepared using a microfluidic device. We explored the reconfiguration of the CLC molecules confined in droplets in the presence of 1,2-diauroyl-sn-glycero3-phosphatidylcholine (DLPC) phospholipid. Cross-polarized optical microscopy and spectrometry techniques were employed to monitor the effect of droplet size and DLPC concentration on the structural reorganization of the CLC molecules. Our results showed that in the presence of DLPC, the chiral LC droplets transition from planar to homeotropic ordering through a multistage molecular reorientation. However, this reconfiguration process in the low-chirality droplets happened three times faster than in high-chirality ones. Applying spectrometry and image analysis, we found that the change in the chiral droplets’ Bragg reflection can be correlated with the CLC–DLPC interactions. 

Abstract Blue phases (BPs), formed through the self‐assembly of chiral liquid crystal molecules into 3D nanolattices with cubic symmetries, exhibit dynamic photonic bandgaps in the visible spectrum, offering transformative opportunities for advanced optical circuits, sensing and communication technologies. However, their thermal stability is restricted to a narrow temperature range (0.5–1.0 K), limiting practical applications. Polymer stabilization of bulk BPs has extended thermal stability but often compromises the dynamic behavior essential for fast‐response functionalities. Here, experimental and computational approaches are integrated to investigate the effect of curvature and interfacial interactions on BP polymer stabilization. It is demonstrated that photo‐polymerization of reactive monomers within BP microdroplets produces polymer shells, a few hundred nanometers thick, featuring BPs disclination network nano‐architecture. This nano‐architected shell provides surface topology and anchoring conditions to direct BP nucleation and growth, with the degree of curvature dictating the stabilized BP lattice structure within microdroplets. Remarkably, while enhancing thermal stability across a broad temperature range, this polymer shell enables reconfigurable crystal‐to‐crystal transformations in stabilized BP droplets. This work introduces a novel approach to tailoring BP properties by leveraging curvature, confinement, and interfacial interactions to create thermally stable, reconfigurable photonic crystals, paving the way for adaptive sensors and next‐generation fast‐response optical devices. 

Liquid crystals are known to exhibit intriguing textures and color patterns, with applications in display and optical technologies. This work focuses on chiral materials and examines the palette of morphologies that arises when microdroplets are deformed into nonspherical shapes in a controllable manner. Specifically, geometrical confinement and mechanical strain are used to manipulate orientational order, phase transitions, and topological defects that arise in chiral liquid crystal droplets. Inspired by processes encountered in nature, where insects and animals often rely on strain and temperature to alter the optical appearance of dispersed liquid crystalline elements, chiral droplets are dispersed in polymer films and deformation induced by uniaxial or biaxial stretching. Our measurements are interpreted by resorting to simulations of the corresponding systems, thereby providing an in-depth understanding of the morphologies that arise in these materials. The reported structures and assemblies offer potential for applications in smart coatings, smart fabrics, and wearable sensors. 

Liquid crystals are important components of optical technologies. Cuboidal crystals consisting of chiral liquid crystals−the so-called blue phases (BPs),are of particular interest due to their crystalline structures and fast response times, but it is critical that control be gained over their phase behavior as well as the underlying dislocations and grain boundaries that arise in such systems. Blue phases exhibit cubic crystalline symmetries with lattice parameters in the 100 nm range and a network of disclination lines that can be polymerized to widen the range of temperatures over which they occur. Here, we introduce the concept of strain-controlled polymerization of BPs under confinement, which enables formation of strain-correlated stabilized morphologies that, under some circumstances, can adopt perfect single-crystal monodomain structures and undergo reversible crystal-to-crystal transformations, even if their disclination lines are polymerized. We have used super-resolution laser confocal microscopy to reveal the periodic structure and the lattice planes of the strain and polymerization stabilized BPs in 3D real space. Our experimental observations are supported and interpreted by relying on theory and computational simulations in terms of a free energy functional for a tensorial order parameter. Simulations are used to determine the orientation of the lattice planes unambiguously.The findings presented her eoffer opportunities for engineering optical devices based on single-crystal, polymer-stabilized BPs whose inheren tliquid nature, fast dynamics, and long-range crystalline order can be fully exploited.