Thermo Scientific Pierce BGG Protein Assay Standards are high-quality reference samples for generating accurate standard curves and calibration controls in total protein assays.
These bovine gamma globulin (BGG) solutions are protein concentration reference standards for use in BCA, Bradford and other protein assay protocols. BGG is an accepted reference protein for total protein quantitation of purified antibodies or immunoglobulin-rich samples. The IgG standard is precisely formulated at 2mg/mL in an ultrapure 0.9% sodium chloride (saline) solution. The concentration of the stock solution of purified BGG (Fraction II) is calibrated by direct comparison to an internal standard to ensure lot-to-lot consistency and accuracy. The product is available in two convenient package formats: 1mL glass ampules and a set containing seven ready-to-use dilutions (3.5mL each).
- Antibody standard – best reference standard for immunoglobulin quantitation in colorimetric protein assays
- Bradford standard – best general protein standard in coomassie-based (Bradford) protein assays
- Pure and stable – supplied in ultrapure 0.9% saline solution with 0.05% sodium azide; room temperature stable
- Accurate and consistent – precisely formulated at 2.00 +/-0.03mg/mL, ensuring excellent lot-to-lot consistency
- Convenient – choose a package of 1mL ampules or a complete set containing seven ready-to-use dilutions
- Protein assay immunoglobulin quantitation standard (Coomassie-Bradford Assay, etc.)
- Antibody recovery control for desalting and other column procedures
- Loading control for SDS-PAGE
- General calibration of spectrophotometer UV-lamp (absorbance at 280nm)
Selection of a protein standard is potentially the greatest source of error in any protein assay. The best choice for an antibody quantitation standard is a purified, known concentration of the specific immunoglobulin being tested. Often this is not available or it is too expensive to use as a standard. In such cases, the best standard is one that will produce a representative color response curve with the selected protein assay and is readily available to any researcher. BGG provides this function for all kinds of immunoglobulin samples, including IgG.
For greatest accuracy in estimating total protein concentration in unknown samples, it is essential to include a standard curve each time the assay is performed. This is particularly true for the protein assay methods that produce non-linear standard curves. Deciding on the number of standards and replicates used to define the standard curve depends upon the degree of non-linearity in the standard curve and the degree of accuracy required. In general, fewer points are needed to construct a standard curve if the color response is linear. Typically, standard curves are constructed using at least two replicates for each point on the curve.
Tech Tip #57: How to use a protein assay standard curve
Tech Tip #6: Extinction coefficients guide
Review of Protein Assay Methods
Bovine Serum Albumin (BSA) Standards (best for BCA assays and non-antibody samples)
Coomassie (Bradford) Protein Assay Kit
Coomassie Plus (Bradford) Assay Kit
All Pierce Protein Assay Kits and Reagents