A MODEL ONLINE FLOW-INJECTION FLUORESCENCE IMMUNOASSAY USING A PROTEIN-A IMMUNOREACTOR AND LUCIFER YELLOW

A heterogeneous on-line fluorescence immunoassay has been developed fo r a model analyte (transferrin) using a flow injection analysis system containing a controlled pore glass protein A immunoreactor. Lucifer y ellow VS (LYVS) a 4-aminonaphthalimide with a large stokes shift and p H independence was the fluorophore. For each assay the antibody-protei n A reaction takes place at near neutral pH, and the complexes are elu ted at acid pH. Transferrin levels in human serum has been determined by this method, and good within assay variations have been achieved.