Determination of avidin and streptavidin by a modified Bradford method

Underestimation of avidin and streptavidin by the Bradford method can be alleviated by carrying out the reaction at 100 degrees C for 10-15 min, and the protein values thus obtained match very well with those of biotin-binding assays. "Thermal modification" is applicable to "standard" and "micro" versions of the method and has no effect on the spectral and stability characteristics of the protein-dye complexes.