The Lowry protein assay is a biochemical assay for determining the total level of protein in a solution. The total protein concentration is exhibited by a color change of the sample solution in proportion to protein concentration, which can then be measured using colorimetric techniques.
The improved Lowry protein assay utilizes stable reagents and offers enhanced sensitivity and a more accurate estimation of protein content. It circumvents interference from colored pigments and other substances. The assay is carried out on the PCA precipitated protein pellet after neutralization (Na2CO3 and NaOH), solubilization (Triton-NaCl), decolorization (H2O2), and pyruvate treatment.