Adenosine triphosphate (ATP) and zinc(II) ions responsive pyrene based turn-on fluorescent probe and its application in live cell imaging

Abstract

A novel highly selective and sensitive turn-on fluorescent chemosensor PCE to recognize Zn²⁺ has been developed. The sensor PCE displays a remarkable fluorescent enhancement at 456 nm (λ_ex = 340 nm) with Zn²⁺ without the interference of other biologically important relevant metal ions in aqueous acetonitrile solution. Job's plot and mass spectral studies divulge such the interaction of PCE by Zn²⁺ was 1:1 binding stoichiometry. The association constant and detection limit of PCE to recognize Zn²⁺ was found to be 0.948 × 10⁴ M^-1 and 4.82 × 10^-7 M respectively. The nature of turn-on fluorescence sensor was supported by TD-DFT calculations. And the synthesized probe PCE was able to image intracellular Zn²⁺ in living cells using confocal imaging techniques. PCE-Zn ensemble showed the remarkable fluorescence enhancement with ATP selectively among other biologically important phosphates. ³¹P NMR experiments suggesting that the triphosphates unit of ATP is intact with the PCEZn. PCE-Zn ensemble can be utilized for monitoring ATP in live cells.

Keywords: ATP sensor; Chemosensor; Imaging; Pyrene; Zinc.