Pierce Protein Assay

The Pierce Protein Assay is a method of protein quantification. It provides quick estimation of the protein amount in a given sample.^[1]

Protocol

The assay is separated into three main parts: preparation of the Diluted Albumin (BSA) Standards, preparation of the bicinchoninic acid (BCA) working reagent, and quantification of proteins (using either test tube 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 detergents or other reducing agents. 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

^ "Protein Assay Handbook" (PDF). Life technologies. Retrieved 9 April 2015.

Analytical reagents and tests

Metals

Aluminon
Xylenol orange

Sugars, fats, and proteins

Sugars & starches	Barfoed's test (Monosaccharides) Benedict's reagent (reducing sugars etc) Bial's test (pentoses) Aniline acetate test (pentoses) Starch indicator Molisch's test (carbs) Tollens' reagent (reducing sugars) Fehling's solution (reducing sugars)
Proteins & amino acids	Biuret test (proteins) Bicinchoninic acid assay (concentration) Bradford protein assay (concentration) Lowry protein assay (total protein) Pierce Protein Assay (total protein) Tollens' reagent (aldehyde & ketones) Fehling's solution (aldehyde & ketones) Van Slyke determination (amino acids) Sakaguchi test (arginine) Xanthoproteic reaction (proteins)
Fats	Sudan stain (lipids)