The Pierce Protein Assay is a method of protein quantification. It provides quick estimation of the

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

amount in a given sample.

Protocol

The

assay An assay is an investigative (analytic) procedure in laboratory medicine, mining, pharmacology, environmental biology and molecular biology for qualitatively assessing or quantitatively measuring the presence, amount, or functional activity ...

is separated into three main parts: preparation of the Diluted

Albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All of the proteins of the albumin family are water- soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Alb ...

(BSA) Standards, preparation of the bicinchoninic acid (BCA) working reagent, and quantification of proteins (using either

test tube A test tube, also known as a culture tube or sample tube, is a common piece of laboratory glassware consisting of a finger-like length of glass or clear plastic tubing, open at the top and closed at the bottom. Test tubes are usually placed in s ...

or microplate procedure).

Advantages and disadvantages

Advantages

This method is able to detect as low as 25 μg/ml and up to 2000 μg/ml of protein in a 65 ul sample, using standard protocol. This method may be preferred for samples containing

detergent A detergent is a surfactant or a mixture of surfactants with Cleanliness, cleansing properties when in Concentration, dilute Solution (chemistry), solutions. There are a large variety of detergents. A common family is the alkylbenzene sulfonate ...

s or other

reducing agent In chemistry, a reducing agent (also known as a reductant, reducer, or electron donor) is a chemical species that "donates" an electron to an (called the , , , or ). Examples of substances that are common reducing agents include hydrogen, carbon ...

s. This method has a fast detection speed and low protein-to-protein variability in comparison to the BCA or Coomassie (Bradford) Assays. This method has a stable end point.

Disadvantages

This method has greater protein-to-protein variability than the BCA Assay.

References

{{Analytical reagents Biochemistry methods Chemical tests