MCE Renilla-Firefly Luciferase Dual Assay Kit contains high-purity D-Luciferin, coelenterazine and proprietary reaction buffer. The Firefly Luciferase Working Solution is first added to the sample. This reagent contains D-Luciferin which can produce Firefly luciferase bioluminescence. Next, the Renilla Luciferase Working Solution is added to the same sample. It quenches the Firefly luciferase bioluminescence and produce Renilla luciferase bioluminescence. The light production of both reactions can be conveniently measured on a luminometer.