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Lewis Acid-Triggered Spatiotemporally Controllable Ring Opening in a Classic Rhodamine Featuring Φ = 95% Emission
Quanchun Sun1,2, Liancheng He1,2, Tao Wang1
1State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing 210023 P. R. China.
Small Science
|February 20, 2026
Summary
Researchers developed a new Lewis acid method to activate rhodamine fluorophores, enhancing their fluorescence without damage. This breakthrough offers a nondestructive pathway for improved material engineering and biomedical applications.
Area of Science:
- Organic Chemistry
- Materials Science
- Biomedical Engineering
Background:
- Rhodamine derivatives are crucial fluorophores in materials science and biomedical research.
- Traditional methods for activating rhodamine's spirolactone ring often degrade fluorescence and are synthetically complex.
Purpose of the Study:
- To introduce a novel Lewis acid-assisted strategy for activating rhodamine fluorophores.
- To overcome limitations of conventional proton-mediated activation and synthetic optimization.
Main Methods:
- Employing Lewis acid coordination to facilitate reversible spirolactone ring opening in rhodamine systems.
- Investigating photocontrol over the ring opening process via Lewis acid complexation.
Main Results:
- Achieved significant fluorescence enhancement with quantum yields up to 95% and extended excited state lifetimes.
- Demonstrated precise photocontrol over the activation process.
- Successfully converted nonemissive spirolactone forms into highly luminescent Lewis acid complexes.
Conclusions:
- The Lewis acid-assisted strategy provides a nondestructive activation pathway for rhodamine fluorophores.
- This method enhances fluorescence performance while preserving molecular integrity.
- Paves the way for advanced applications in material engineering and biomedical research.
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