title: FRET versus PET: ratiometric chemosensors assembled from naphthalimide dyes and crown ethers.
abstract: Novel bi-chromophoric naphthalimide derivatives containing benzo-15-crown-5 and N-phenyl-aza-15-crown-5 receptor moieties BNI2 and BNI3 were designed and prepared. Significant Förster resonance energy transfer (FRET) from donor (D) amido-naphthalimide to acceptor (A) amino-naphthalimide chromophores as well as photoinduced electron transfer (PET) between the N-aryl receptor and amido-naphthalimide fragment was revealed by the steady-state and time-resolved UV/Vis absorption and fluorescence spectroscopy. Upon the addition of alkaline-earth metal perchlorates to an acetonitrile solution of ligands, FRET mediated fluorescence enhancement was observed, which was a result of inhibition of the PET competitive deactivation pathway. The studied compounds provide an opportunity to register a two-channel fluorescence response upon selective excitation of either of the photoactive units and, thus, might be of interest as ratiometric probes.
authors.affiliation: A. N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences (INEOS RAS), 119991, Vavilova str. 28, Moscow, Russia. pavel@ineos.ac.ru.
authors.forename: Pavel A
authors.initials: PA
authors.lastname: Panchenko
authors.forename: Yuri V
authors.initials: YV
authors.lastname: Fedorov
authors.forename: Olga A
authors.initials: OA
authors.lastname: Fedorova
authors.forename: Gediminas
authors.initials: G
authors.lastname: Jonusauskas