February 19, 2024
Keio University
A research group led by Professor Kenjiro Hanaoka of the Keio University Faculty of Pharmacy has discovered new fluorescent properties of rhodamine fluorescent dyes, which are widely used in fluorescence imaging.
Rhodamine fluorescent dyes, known for nearly a century, have been used for fluorescence imaging in living cells and animals. In fluorescence imaging, fluorescent probes that recognize target biomolecules and switch their fluorescence from off to on are essential, and their development has been actively pursued since the 1980s. Although the fluorescent properties of rhodamine dyes were thought to be fully understood, this research group succeeded in almost completely quenching their fluorescence by inducing intramolecular “twisting.” They named this phenomenon steric repulsion-induced twisted intramolecular charge transfer (sr-TICT). Based on this finding, they successfully developed a fluorescent probe that exhibits a more than 100-fold increase in fluorescence in response to the activity of CYP3A4, a major drug-metabolizing enzyme. Furthermore, using this fluorescent probe, they succeeded in the separation and purification of mature hepatocytes and intestinal epithelial cells differentiated from human iPS cells.
It is expected that the newly developed fluorescent probe will contribute to drug discovery and regenerative medicine in the future. The results of this research were published in the international scientific journal “Science Advances” on February 16, 2024 (US Eastern Time).
For the full press release, please see below.