Abstract
A fluorescent receptor, isocyanatopropyl trimethoxysilane grafted 9-amino acridine (AcI), was synthesized and characterized by elemental analysis, FTIR and NMR spectroscopy. Photophysical properties and pH-dependent fluorescence behavior of AcI were investigated and its complex stoichiometry with uranyl ion was elucidated. Change in fluorescence emission of AcI with pH of the solution was observed and pKa value was determined by using integrated emission intensity versus pH. It was found that AcI exhibited fluorescence enhancement, which can be attributed to an internal charge transfer (ICT) mechanism, upon titration with uranyl ions in mixture of ethanol-buffer solution while the fluorescence emission of AcI was not affected by addition of other divalent transition metal ions except mercury (II) ions. On the other hand, the both fluorescence and UV-vis titration measurements revealed unique selectivity for uranyl ions over the interfering mercury (II) ions. The spectrofluorometric titration clarified that uranyl interacted with AcI to form AcI2(UO2 2+)3 (2:3) complex structure with an apparent association constant of K=7.41×106 M-2/3. The interference effect of some cations on fluorescence enhancement exhibited by complex was also tested.
Original language | English |
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Pages (from-to) | 727-733 |
Number of pages | 7 |
Journal | Journal of Fluorescence |
Volume | 24 |
Issue number | 3 |
DOIs | |
Publication status | Published - May 2014 |
Funding
Acknowledgments We thank research project supported by Istanbul Technical University (BAP, Project No: 36236).
Funders | Funder number |
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British Association for Psychopharmacology | 36236 |
Istanbul Teknik Üniversitesi |
Keywords
- Complex stoichiometry
- Fluorescent receptor
- ICT
- Uranyl ion