Use of avidin-biotin-peroxidase complex (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled antibody (PAP) procedures

J Histochem Cytochem. 1981 Apr;29(4):577-80. doi: 10.1177/29.4.6166661.


The use of avidin-biotin interaction in immunoenzymatic techniques provides a simple and sensitive method to localize antigens in formalin-fixed tissues. Among the several staining procedures available, the ABC method, which involves an application of biotin-labeled secondary antibody followed by the addition of avidin-biotin-peroxidase complex, gives a superior result when compared to the unlabeled antibody method. The availability of biotin-binding sites in the complex is created by the incubation of a relative excess of avidin with biotin-labeled peroxidase. During formation of the complex, avidin acts as a bridge between biotin-labeled peroxidase molecules; and biotin-labeled peroxidase molecules, which contains several biotin moieties, serve as a link between the avidin molecules. Consequently, a "lattice" complex containing several peroxidase molecules is likely formed. Binding of this complex to the biotin moieties associated with secondary antibody results in a high staining intensity.

Publication types

  • Comparative Study

MeSH terms

  • Avidin*
  • Biotin*
  • Humans
  • Immunoenzyme Techniques*
  • Ovalbumin* / analogs & derivatives
  • Peroxidases
  • Staining and Labeling


  • Avidin
  • Biotin
  • Ovalbumin
  • Peroxidases