1206101-93-0Relevant academic research and scientific papers
Specific ca2+ fluorescent sensor: Signaling by conformationally induced pet suppression in a bichromophoric acridinedione
Ashokkumar, Pichandi,Ramakrishnan, Vayalakkavoor T.,Ramamurthy, Perumal
experimental part, p. 5941 - 5947 (2010/03/25)
A series of acridinedione-based bichromophoric podand systems 1a-c were synthesized and characterized. Among these, bichromophore 1c shows specific binding of Ca2+ in the presence of other biologically important metal ions like Na+, K+, Mg2+, and Zn2+, The selective complexation was proved by steady-state emission, time-resolved emission, and 1H NMR titration. Signaling of the binding event was achieved by Ca2+-induced folding of the bichromophore, resulting in PET suppression in the acridinedione chromophore. Involvement of a PET process in the optical signaling was confirmed by comparing bichromophores 1a-c with non-PET compound 2 -and monochromophore model compound 3. Non-PET compound 2 failed to give optical response upon Ca2+ binding as a result of the absence of a POT process in the Ca2+-bound complex. Monochromophore 3 shows a similar optical response, which is the same as that in 1c. Titration of the metalion-bound complex of 1c with EDTA released the metal ion from the complex, thereby regaining the original photophysical properties of the bichromophore.
