Separation-Free Enzyme Immunoassay for Haptens

  • Anna Jaklitsch


Separation-free (homogeneous) enzyme immunoassays (Emit®) were first developed at the Syva Research Institute in the early 1970s. Their discovery was that binding of an anti-drug antibody to an enzyme labeled with the same drug, modulated (inhibited or activated) catalytic activity. Thus a competitive immunoassay can be developed in which drug in the sample and enzyme-labeled drug compete for antibody. Modulation of enzyme activity is directly related to the analyte concentration in the sample and is monitored without separation of antibody bound and unbound fractions. This principle was later extended to a variety of enzymes and also applied to the measurement of hormones (Ullman et al., 1979) and proteins (Gibbons et al., 1980).


Therapeutic Drug Monitoring Dextran Sulfate Enzyme Conjugate Toxicology Assay Oxidize nicotinamIde Adenine Dinucleotide 
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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • Anna Jaklitsch
    • 1
  1. 1.SYVA CompanyPalo AltoUSA

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