首次实现基于罗丹明染料分子自身的圆偏振发光及其开关，并发现不同手性可以染色不同的细胞器。

Circularly Polarized Luminescence Switching, Chirality Self-Sorting, and Cell Imaging of Chiral Rhodamine Dyes

Lang Qu, Xueman Zhou, Jintong Song, Bao Zhang, Qingping Yang, Xiangge Zhou, Jin Liu,* and Haifeng Xiang*

Adv. Optical Mater. 2023, 11, 2300779  doi: 10.1002/adom.202300779

Rhodamine dyes, as star molecules of fluorescent dyes, are critical tools in modern analytical and biochemical research. However, switching their chiroptical properties still remains a big challenge because of the absence of a suitable synthesis method to incorporate through conjugation a chiral fragment into the chromophore core of rhodamine. Herein, a simple and straightforward way is utilized to link two rhodamine chromophores by different chiral bridges. The conjugated RRR/SSS birhodamine dyes with one axial chirality, which is constructed directly by two rhodamine chromophores, and two spirocyclic chiralities show the interesting circular dichroism and circularly polarized luminescence switching and lysosome-targetable properties. On the other hand, the unconjugated RR/SS birhodamine dyes with two chiral carbons do not have such chiroptical switching properties but do have different amazing cellular staining properties. The RR birhodamin dye can stain both lysosomes and mitochondria, but SS birhodamine dye can stain lysosomes only. Moreover, the mechanisms of chiroptical switching and diastereoselectivity are investigated as well, based on single-crystal structures and density functional theory calculations. Therefore, a new platform is afforded here in designing chiral dyes for chiroptical switching and cell imaging applications.