Question

Compare and contrast the Biuret reaction, BCA, and Bradford assay in chemical detail. Explain if there are any pros or cons of each method, and why a protein scientist would prefer one method to another. Finally, suggest and describe other types of protein quantifications methods not mentioned here.

Answer 1

The BCA Protein Assay is a popular method for colorimetric detection and the quantitation of total protein. The new Pierce Rapid Gold BCA Protein Assay provides the comparable accuracy to the standard BCA assay, but requires only a five minute incubation time at room temperature. These BCA Protein Assays have a unique advantage over the Modified Lowry Protein Assay and any of the Coomassie dye–based assays–they are compatible with samples that contain up to 5% surfactants . Compared to most dye-binding methods, the BCA Assays are affected much less by protein compositional differences, providing greater protein-to-protein uniformity.