Luminescent Nanocomposites of Liquid Crystals and Carbon Dots in Microfluidic Channels: Effects of Walls, Dynamics,...

Microfluidic confinement offers new opportunities for tailoring properties of nanomaterials by applying specific dynamic and wall effects. A vibrant approach is integration of microfluidic channels with lyotropic liquid crystals and luminescent additives, which offer a variety of tunable supramolecular organizations for applications in nanotechnology and biomedicine. This paper focuses on analyzing nanoscale and microscale properties of the nanomaterials represented by tetraethylene glycol and decaethylene glycol monododecyl ethers with integrated carbon dots. Orienting impact of microchannel surfaces was found to be responsible for additional microscale ordering of the intrinsic lamellar and hexagonal structures of these composites after the phase transition from the isotropic liquid to the liquid crystalline state. Controlled and varied shear stress resulted in additional planar orientation of the composites and provided them with anisotropic luminescence properties, which were not demonstrated by macroscopic samples. Incorporation of a bioactive compound into the liquid crystalline matrix allowed obtaining the specific and detectable anisotropic luminescence response of the nanomaterials. The datasets comprising hundreds of polarized microscopy images were successfully used for training the neural network and accurate recognition of the liquid crystal type in the composites. The results will contribute to developing AI-compatible microfluidic chips, which simulate the biological capillary environment and allow for tuning properties of luminescent nanomaterials for drug delivery and biomedical applications.