Luminescent Europium complex based on7-hydroxy-coumarin-4-aceticas ligand was investigated as a probe
for the detection of organophosphorus pesticides. The complex exhibited an interesting action towards Crotoxyphos
pesticide. The luminescence of the Eu(III)-7-hydroxy-coumarin-4-acetic was remarkably enhanced by gradual addition
of Crotoxyphos. Limit of detection (LOD) = 1.86 μM and limit of quantitation (LOQ) = 6.19μM. Binding constant at
different temperatures was calculated according to Benesi-Hildebrand equation. The thermodynamic parameters DH, DS
and DG were calculated for characterization of the nature of force due to interaction of the complex with Crotoxyphos.
Finally, the effect of interfering anion and cations that naturally occur in water and soil was studied, in addition;
interference of some pesticides was studied.