The combination of responsive materials with 3D printing can lead to functional materials and devices for use in health, biofabrication, and biosensing. Here, we utilized an all-aqueous two-phase system made from chitosan and carrageenan to create all-water emulsion bodies, a groundbreaking group of encapsulated emulsions for possible drug delivery. Specifically, we described the development of an original all-aqueous cholesteric bicontinuous liquid crystal (LC) emulsion, which was accomplished by homogenization of a rod-like cellulose nanocrystal (CNC) with two thermodynamically immiscible, phase-separating carrageenan and chitosan solutions. Stable water-in-water emulsions were effectively prepared by mixing the respective CNC/biopolymer dispersions, showing micrometric CNC/chitosan dispersed droplets and a CNC/carrageenan continuous phase. The LC-based emulsion showed a confined 3D percolating bicontinuous network with cholesteric self-assembly of CNC within the carrageenan phase, while the nanoparticles in the chitosan phase remain isotropic. After laser 3D printing of freeze-dried LC-based emulsion, 3D porous printlets loaded with curcumim were produced with a dual stimuli response toward temperature and redox. The curcumin-loaded 3D printlets exhibited superior thermosensitive properties and maintained a sustained drug release profile, exhibiting much greater on-demand release mode at human body temperature. Notably, the 3D printlets demonstrated a gated response in an aqueous environment, showcasing potential advancements in the realms of supramolecular sensors and drug delivery systems.
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