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Updated: Aug 2, 2025

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
DNA-induced circularly polarized luminescence of helicene racemates
Fuwei Gan1, Peng Yang1, Juncong Liang1
1School of Chemistry and Chemical Engineering, Zhangjiang Institute for Advanced Study, Frontiers Science Center for Transformative Molecules, State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai, People's Republic of China.
Abstract:
Enantiopure helicenes have been extensively investigated due to their outstanding chiroptical properties, while helicene racemates are considered as chiroptically silent. Here, we describe a facile method to produce circularly polarized luminescence (CPL) from helicene racemates via supramolecular association with DNA in aqueous solution. Racemic cationic helicene derivatives are immobilized in the grooves of commercially available double-stranded right-handed DNA, and the discrimination of left- and right-handed helicenes by chiral DNA is monitored by single molecule force spectroscopy. This subsequently leads to the generation of prominent CPL with dissymmetric factor |glum | of close to 0.01, which is approximate to enantiopure helicenes. The strategy developed in this work avoids the tedious and expensive chiral resolution process and provides a distinctive insight into the fabrication of CPL-emitting systems.
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