Inventors:
George C. Saunders - Espanola NM
Assignee:
United States Department of Energy - Washington DC
International Classification:
G01N 3353, G01N 33543, G01N 33544, G01N 33546
Abstract:
A method of measuring the result of a binding assay that does not require separation of fluorescent smaller particles is disclosed. In a competitive binding assay the smaller fluorescent particles coated with antigen compete with antigen in the sample being analyzed for available binding sites on larger particles. In a sandwich assay, the smaller, fluorescent spheres coated with antibody attach themselves to molecules containing antigen that are attached to larger spheres coated with the same antibody. The separation of unattached, fluorescent smaller particles is made unnecessary by only counting the fluorescent events triggered by the laser of a flow cytometer when the event is caused by a particle with a light scatter measurement within a certain range corresponding to the presence of larger particles.