Separation-free dual solid phase enzyme immunoassay for macromolecules

The dual solid phase enzyme immunoassay system, DSPEIA, has characteristics of both herero- and homogeneous enzyme immunoassay. DSPEIA relies on the partitioning of an enzyme conjugate (biotin-glucose-6-phosphate dehydrogenase-antibody) between two solid phases of polystyrene latex bound avidin and polystyrene latex bound antigen. When enzyme conjugate binds to latex-antigen, the enzyme activity is unaffected, whereas binding to latex-avidin inhibits enzymatic activity. The assay utilizes a competition between this conjugate and analyte antibody for the latex-antigen. DSPEIA requires no separation step and is applicable to macromolecules.