Energy transfer from adenosine 5′-triphosphate to europium and interaction between europium and adenosine 5′-triphosphate and adenosine 5′-monophosphate at room temperature

Complex formation between Eu³⁺ and ATP was demonstrated from the appearance of "hypersensitive" transitions in the Eu³⁺ ion. As a result of complex formation the quantum efficiencies of europium ⁵D₀ fluorescence are increased. Energy transfer from ATP to Eu³⁺ occurs via an exchange mechanism between the triplet level or excimer level of ATP and the ⁵L₆ level of Eu³⁺. The relative population of the ⁵L₆ excited level of Eu³⁺ by energy transfer is calculated.