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Updated: Jun 14, 2025

Controllable Ion Channel Expression through Inducible Transient Transfection
Published on: February 17, 2017
Steric Gating of Excited-State Channel: Controllable AIE/RTP Switching through Tuning π-Bond Twisting
Hongli Xue1,2,3,4, Changqing Ye2,3, Haiyang Huang2,5
1College of Chemistry, Fuzhou University, Fuzhou, Fujian 350108, P. R. China.
Abstract:
We demonstrate steric control of excited-state channel in π-conjugated 1,1'-bibenzo[f]isoindolylidenes through substituent-engineered C═C bond twisting. By tuning substituent bulkiness (R2), we achieve dynamic switching between aggregation-induced emission and dilute/dual-state fluorescence. The mechanical gating of biradicaloid isomerization channels was confirmed by variable-temperature NMR and EPR spectroscopy. The π-twisting activates low-energy CI pathways for AIE generation, while excessive bulkiness relocks molecular conformation, enabling solution-phase emission. This steric gating mechanism, validated by TD-DFT analysis, demonstrates controllable fluorescence and phosphorescence by modulating the π-twisting feasibility of the central C═C bond, offering a novel strategy for designing advanced aggregation-induced emission (AIE) and RTP-active molecules.
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