Scintillation proximity assay

Scintillation proximity assay (SPA) is an assay development and biochemical screening that permits the rapid and sensitive measurement of a broad range of biological processes in a homogeneous system. The type of beads that are involved in the SPA are microscopic in size and within the beads itself, there is a scintillant which emits light when it is stimulated. Stimulation occurs when radio-labelled molecules interact and bind to the surface of the bead. This interaction will trigger the bead to emit light, which can be detected using a photometer.