6533b7d0fe1ef96bd125a6d0
RESEARCH PRODUCT
Strong Emission Enhancement in pH-Responsive 2:2 Cucurbit[8]uril Complexes
Stefan SchoderHendrik V. SchröderLuca CeraRakesh PuttreddyArne GüttlerUte Resch-gengerKari RissanenChristoph A. Schalleysubject
Charge transferLuminescenceintramolecular motioncucurbiturilsluminesenssihost–guest systemsfluoresenssisupramolekulaarinen kemiafluorescence enhancementBiological materialsFluorophoresdescription
Organic fluorophores, particularly stimuli-responsive molecules, are very interesting for biological and material sciences applications, but frequently limited by aggregation- and rotation-caused photoluminescence quenching. A series of easily accessible bipyridinium fluorophores, whose emission is quenched by a twisted intramolecular charge-transfer (TICT) mechanism, is reported. Encapsulation in a cucurbit[7]uril host gave a 1:1 complex exhibiting a moderate emission increase due to destabilization of the TICT state inside the apolar cucurbituril cavity. A much stronger fluorescence enhancement is observed in 2:2 complexes with the larger cucurbit[8]uril, which is caused by additional conformational restriction of rotations around the aryl/aryl bonds. Because the cucurbituril complexes are pH switchable, this system represents an efficient supramolecular ON/OFF fluorescence switch. peerReviewed
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2019-01-01 |