Abstract: A method for performing a rapid, homogenous assays for monitoring the reactions of a binding target, by immobilizing a fluorescent-capable chelate complex that is derivatized so as to posses recognition binding ligands, labeling the complex with a labeled second chelator that is added to the assay thereby forming a fluorescent mixed chelate, and measuring the fluorescent mixed chelate, whereby the measurement of the label enable monitoring of the reaction of the binding target. A rapid assay for performing the above method including a first chelating molecule, a fluorescent-capable ion complexed with the first chelating molecule, a second chelating molecule for reacting with the fluorescent-capable ion complexed with the first chelating molecule, and a measuring device for measuring fluorescent resulting from the second chelating molecule reacting with the fluorescent-capable ion complexed with the first chelating molecule.