Lead Halide Perovskite Nanocrystals–Phospholipid Micelles and Their Biological Applications: Multiplex Cellular Imaging and in Vitro Tumor Targeting

Lead halide perovskite nanocrystals (NCs) are promising optical materials in many fields. However, their poor moisture stability, significant toxicity, and difficulty to be further functionalized greatly hinder their applications in bioimaging. Here, a universal strategy is demonstrated by simply encapsulating CsPbX₃ (X = Cl, Br, I) NCs into phospholipids to achieve CsPbX₃-phospholipid micelles (CsPbX₃@phospholipid) as probes for multiplex encoding cellular imaging or tumor-targeted imaging. The layer of phospholipids endows CsPbX₃ NCs with superior water-resistant characteristics, the ability to be further biofunctionalized, and greatly improved biocompatibility. The CsPbX₃@phospholipid micelles exhibited strong luminescence with narrow fwhm in water for more than four months. Specifically, even after being modified with folic acid, the bright fluorescence of the micelles was well retained, which were employed for the targeting of Hela cells. Finally, the greatly reduced toxicity of the CsPbX₃@phospholipid micelles was verified using HeLa cells and zebrafish as in vitro and in vivo models, respectively.