A new luminescent bio-probe of Europium(III)-complex for sensing some biomolecules and CT-DNA

Here, we demonstrated a bio-probe based on Europium(III)-8-allyl-2-oxo-2H-chromene-3-carbaldehyde (AOCC) complex for sensing of N-acetylamino acids, nucleotides, nucleobases and CT-DNA in solution using time-resolved Luminescence method. The stoichiometry of the complex has been optimized to be 1:3 metal: ligand ratio. The limits of detection were in the range of 0.044 - 0.13 μM. The binding constants (K) and thermodynamic parameters of biomolecules under examination with Eu (III)–(AOCC)3 complex have been determined. Selectivity of Eu(III)-(AOCC)3 complex towards various biomolecules was studied utilizing ratiometric methods, where the binding affinities of these biomolecules towards Eu(III)-(AOCC)3 complex have been calculated. The binding mode between CT-DNA and Eu(III)-(AOCC)3 has been investigated using steady-state luminescence and viscosity method. The luminescence emission of this complex was found to be modulated to different degrees when interacting biomolecules under investigation and DNA. This can be considered as a model for a sensor for detecting these biologically compounds.