Disadvantages
The Bradford assay is linear over a short range, typically from 0 µg/ml to 2000 µg/ml, often making dilutions of a sample necessary before analysis.
It is also inhibited by the presence of detergents.
Much of the non-linearity stems from the equilibrium between two different forms of the dye which is perturbed by adding the protein. The Bradford assay linearizes by measuring the ratio of the absorbances, 595 over 450 nm. This modified Bradford assay is approximately 10 times more sensitive than the conventional one. (Zor & Selinger, 1995)
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