Formation of tactoidal nanoparticle condensates via an aqueous liquid crystal

We report the formation of tactoidal nanoparticle condensates via a method that harnesses particle transport by moving soft phase boundaries between the isotropic and nematic phases of an aqueous liquid crystal. The nanoparticle-rich condensates form within negative tactoids in the biocompatible lyotropic liquid crystal disodium cromoglycate (DSCG) as initially fluidic droplets that subsequently stabilize and can be extracted and resuspended in water. Novel tripolar condensates are also formed and stabilized during the process. Finite element simulations capture the observed negative tactoid morphology and demonstrate the role of liquid crystal elasticity and size on their aspect ratio which we compare with experimental results. To the best of our knowledge, this work introduces the first 3D computational framework for negative tactoids, providing an advancement over previous 2D models to accurately describe the elastic energy landscape of these systems. Our approach establishes a new phase-transition-driven scalable method for generating stable biocompatable assemblies of nanoparticles with unique morphologies.