Biotin avidin interaction

A typical force curve showing the specific avidin-biotin interaction is depicted in figure Bl.20.10. The SFA revealed the strong influence of hydration forces and membrane undulation forces on the specific binding of proteins to membrane-bound receptors [81]. 

In another example, ligands can be biotinylated with a cleavable biotinylation reagent and then incubated with receptor molecules. The resulting complex can be isolated by affinity chromatography on immobilized (strept)avidin. Final purification of the ligand-receptor can be accomplished by cleaving the biotin modification sites while the complex is still bound to the support. The receptor complex thus can be eluted from the column without the usual harsh conditions required to break the avidin-biotin interaction. 

Liposome conjugates may be used in various immunoassay procedures. The lipid vesicle can provide a multivalent surface to accommodate numerous antigen-antibody interactions and thus increase the sensitivity of an assay. At the same time, it can function as a vessel to carry encapsulated detection components needed for the assay system. This type of enzyme-linked immunosorbent assay (ELISA) is called a liposome immunosorbent assay or LISA. One method of using liposomes in an immunoassay is to modify the surface so that it can interact to form biotin-avidin or biotin-streptavidin complexes. The avidin-biotin interaction can be used to increase detectability or sensitivity in immunoassay tests (Chapter 23) (Savage et al., 1992). 

The following sections discuss the concept and use of the (strept)avidin-biotin interaction in bioconjugate techniques. Preparation of biotinylated molecules and (strept)avidin conjugates also are reviewed with suggested protocols. For a discussion of the major biotinylation reagents, see Chapter 11 and Chapter 18, Section 3. 

Use of (Strept)avidin—Biotin Interactions in Assay Systems... 

Guesdon, J.-L., Ternynck, T., and Avrameas, S. (1979) The use of avidin-biotin interaction in lmmunoen-zymatic techniques./. Histochem. Cytochem. 27,1131-1139. 

Ross, S.E., Carson, S.D., and Fink, L.M. (1986) Effects of detergents on avidin-biotin interaction. Biotechniques 4, 350-354. 

Figure 16.4 Proposed structures of multilayer films based on avidin-biotin interactions in case of (A) PAMAM (G4) dendrimer, (B) PAA, (C) PEI [62, 63]...

Giorno R. 1984. A comparison of two immunoperoxidase staining methods based on the avidin-biotin interaction. Diagn Immunol 2 161-166. 

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