The Bradford assay is a form of colorimetric and spectroscopic analysis developed to determine the concentration of a protein; in an aqueous solution. Produced by Marion Bradford in 1976, it was an innovation for its time thanks to various factors including its simplicity, rapid results, reproducibility and a high sensitivity of 0−0.01 mg (Martina and Vojtech, 2015); compared to other tests such as the Lowry and Biuret method, which were successful. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original assay Bradford reagent consists of a mixture of Coomassie Brilliant Blue G-250 dye dissolved in a mixture of phosphoric acid and methanol. The test is based on an absorbance shift of the dye Coomassie Brilliant Blue G-250 where under acidic conditions the red form of the dye is converted to its blue form as it binds to the protein being tested. The binding between the dye and the protein occurs as a result of interactions between basic amino acid residues on the proteins and the dye's lone pair of electrons. This causes the native shape of the protein to distort and expose some of its hydrophobic residues. These hydrophobic residues bind to the non-polar regions of the dye resulting in van der Waals forces. Furthermore, these van der Waals forces lead to the positioning of the positive amino groups closer to the negative charge of the dye, allowing the protein-dye complex to be strengthened through ionic bonding. This results in the red to blue color of the dye that we can detect best at the light wavelength of 595 nm. Overall this demonstrates that the instability of the Coomassie Brilliant Blue G-250 dye is stabilized by binding to the protein. Therefore, as the protein content increases, more protein-dye complexes are formed and increased staining occurs which can be; therefore the amount of complex present in solution is a measure of protein concentration and can be estimated by reading the absorbance, since there is a direct relationship between the absorbance of a solution and the concentration of soluble proteins. This is known according to the Beer-Lambert law, which states that the concentration of a solute is proportional to the absorbance. Please note: this is just a sample. Get a custom paper from our expert writers now. Get a Custom Assay The objectives of The experiment were as follows: Create a dilution series of protein standard with bovine serum albumin (BSA) and perform the Bradford protein assay on these known protein concentrations. Use the above concentrations to create a measured calibration versus absorbance graph and use this graph to find out the protein concentration in two cell extract samples. Overall, the experiment was conducted to determine the protein concentration in two cell extracts with unknown protein concentration using the Bradford Protein Assay.