Water‐ultrastable perovskite CsPbBr <sub>3</sub> nanocrystals for fluorescence‐enhanced cellular imaging
Caili He, Ziqi Meng, Shuxia Ren, Jian Li, Ye Wang, Hao Wu, Hui Bu, Yù Zhang, Weizhong Hao, Shu‐Lin Chen, Rongrong Yan, Huan Liu, Yufang Zhu, Jinjin Zhao
Abstract
Abstract Metal halide perovskites have attracted much attention in biomedicine because of their excellent fluorescence energy conversion properties; however, poor water‐stability and cytotoxicity limit its applications as a biomedical tracer, especially in cellular imaging. Herein, water‐ultrastable perovskites CsPbBr 3 :Cs 4 PbBr 6 nanocrystals (NCs) encapsulated in chitosan are fabricated successfully using a water‐triggered method. The as‐synthesized CsPbBr 3 :Cs 4 PbBr 6 @CS (chitosan, CS) nanoparticles in water display enhanced fluorescence emission for 35 days. Further, the viability of glioma cells (U87 cells) incubated with different concentrations of CsPbBr 3 :Cs 4 PbBr 6 @CS nanoparticles (0–20 μg·ml −1 ) for 24 h is found to be higher than 90%. In artificial body fluid, analyses using laser confocal microscopy, the standard Cell Counting Kit‐8 (CCK‐8) method, and flow cytometry demonstrated the good water ultrastability and high biocompatibility performance of CsPbBr 3 :Cs 4 PbBr 6 @CS nanoparticles in cellular imaging. Overall, the water‐ultrastable halide perovskites support promising perspectives in biological cell tracing and intelligent medical technology.