Design of redox-responsive fluorescent nanoceria via AIEgen-functionalized dextran for bioimaging

In this study, we report the design and comprehensive physicochemical characterization of a redox-responsive nanoplatform based on cerium oxide nanoparticles (nanoceria) functionalized with thiolated dextran bearing aggregation-induced emission luminogens (AIEgens). The surface engineering strategy, involving covalent grafting via disulfide bonds, was meticulously validated using a multi-technique approach (FTIR, NMR, TGA, and TEM). We demonstrate that this functionalization successfully enhances the colloidal stability of nanoceria while preserving the fluorescence properties of the AIEgens. Furthermore, we evidence a redox-triggered detachment of the polymer shell in the presence of glutathione, mimicking intracellular conditions. This work provides a versatile and well-defined synthetic route to create stable, responsive, and fluorescent nanoceria, representing a significant step toward the development of advanced smart nanomaterials for biomedical applications.