What compounds is the Bradford assay sensitive to?
Unlike other protein assays, the Bradford protein assay is less susceptible to interference by various chemical compounds such as sodium, potassium or even carbohydrates like sucrose, that may be present in protein samples. An exception of note is elevated concentrations of detergent.
How does Bradford assay determine protein concentration?
The Bradford assay is a quick and fairly sensitive method for measuring the concentrations of proteins. It is based on the shift in absorbance maximum of Coomassie Brilliant Blue G-250 dye from 465 to 595 nm following binding to denatured proteins in solution.
What is BSA blood test?
The serum albumin test looks at the levels of albumin in a person’s blood. If the results indicate an abnormal amount of albumin, it may suggest a problem with the liver or kidneys. It may also indicate that a person has a nutrient deficiency.
What is biuret reagent made of?
The Biuret reagent is made of sodium hydroxide (NaOH) and hydrated copper(II) sulfate, together with potassium sodium tartrate, the latter of which is added to chelate and thus stabilize the cupric ions.
What is the principle of biuret test?
Biuret test is based on the reaction of the cupric ions Cu2+ with peptide bonds in an alkaline solution. These ions react with the nitrogen of the peptide bond to form a purple or violet colored complex.
What is the Colour change of biuret test?
Reagents and food testing
| Food sample | Reagent | Colour of positive result |
|---|---|---|
| Reducing sugar | Benedict’s | Brick red precipitate |
| Starch | Iodine | Blue-black |
| Protein/amino acids | Biuret (a mixture of sodium hydroxide and copper sulfate). | Lilac/purple |
| Fat | Ethanol | White emulsion |
Which color is formed in biuret test?
Therefore, the biuret test can be also be used to gauge the amount of protein present in the analyte. In this test, the presence of peptides results in the formation of pale purple coloured (or mauve coloured) coordination compounds of the copper(II) ion (when the solution is sufficiently alkaline).