Non-specific serum binding to streptavidin in a biotinylated peptide based enzyme immunoassay.

Streptavidin coated microtitre wells can be used to provide attachment to biotinylated peptides, regardless of charge and size, for use in an enzyme immunoassay. Considerable non-specific human serum binding to streptavidin at the recommended concentration was noted. The level of binding varied considerably with serum samples and was unrelated to previous streptococcal disease. Strategies used to reduce this phenomenon included pre-absorption of serum with streptavidin and reducing the streptavidin concentration in the wells. Significant reduction in binding was found with a reduction in streptavidin concentration from the recommended concentration of 0.5 ug/well to 0.01 ug/well.