Hydrogen Bonding‐Induced H‐Aggregation for Fluorescence Turn‐On of the GFP Chromophore: Supramolecular Structural Rigidity

• Published in: Chemistry : a European journal Vol. 26; no. 27; pp. 5942 - 5945
• Main Authors: Tsai, Meng‐Shiue, Tsai, Sung‐Yu, Huang, Yi‐Fan, Wang, Chien‐Lung, Sun, Shih‐Sheng, Yang, Jye‐Shane
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 12.05.2020; Wiley Subscription Services, Inc
• Subjects: Agglomeration; Aggregates; aggregation; Chemistry; Chemistry, Multidisciplinary; Chromophores; Fluorescence; gels; Hydrogen bonding; hydrogen bonds; Optoelectronics; Physical Sciences; Quantum efficiency; Rigidity; Science & Technology; supramolecular chemistry; ACTIVATION; fluorescence; gels; CYCLODEXTRIN; CONFINED CHROMOPHORES; EMISSION ENHANCEMENT; PHOTOPHYSICS; aggregation; hydrogen bonds; supramolecular chemistry
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202000358

To turn on the fluorescence of the native green fluorescence protein (GFP) chromophore, 4‐hydroxybenzylidene‐dimethylimidazolinone (HBDI), in an artificial supramolecular system has been a challenging task, because it requires high local environmental rigidity. This work shows that the formation of H‐aggregates of an HBDI‐containing organogelator results in two orders of magnitude fluorescence enhancement (Φf=2.9 vs. 0.02 %), in which the inter‐HBDI OH⋅⋅⋅OH H‐bonds play a crucial role. The aggregation‐induced fluorescence enhancement of HBDI has important implications on the origin of the high fluorescence quantum efficiency of HBDI in the GFP β‐barrel and on the supramolecular strategy for a full fluorescence recovery of HBDI. These results reveal a new approach to designing rigid chromophore aggregates for high‐performance optoelectronic properties. Out of the barrel: The formation of H‐aggregates for an 4‐hydroxybenzylidene‐dimethylimidazolinone (HBDI)‐containing organogelator enhances the fluorescence quantum efficiency by two orders of magnitude, a new record for HBDI in an artificial supramolecular system.