Bovine Serum Albumin (BSA)

Albumin is one of the most extensively used proteins in biological research today. It acts as a powerful antioxidant in cell culture.  It binds, sequesters and stabilizes a variety of molecular species which are often unstable.  This acidic, soluble protein has both high-affinity and secondary binding sites, optimizing the roles that fatty acids, metals, disulfides, and other molecules play in cellular metabolism.

  • Seralab BSA products are prepared by heat shock with the exception of GEM-700-108 which is produced by a modified method of the Cohn cold ethanol fractionation method.
    • Heat shock produces the highest purity BSA product
    • Cohn fractionation method remains the gold standard - this method preserves the biological activity of albumin.
  • Ready-to-buy solutions offer the convenience of not having to solubilise BSA in – house.
  • Available in 20g, 100g and 1kg quantities (lyophilised); or 50mL, 100mL and 1L volumes (solution).
  • Sourced serum or plasma is filtered through a 0.2 μm filter before lyophilisation.
  • All products test negative for viral load ensuring confidence in the integrity of the product.
  • Each batch has been tested and confirmed to have low or undetectable levels of protease, nuclease, endotoxin, globulins, cholesterol, fatty acids and heavy metals or bound ions.
  • With a broad range of BSA products, Seralab has a formulation that suits most applications that require BSA.
  • All Seralab BSA is sourced from the United States and Australia.

There are a lot of choices for bovine serum albumin (BSA). Biologically, albumin exhibits various key functions.  Typically, it is used in cell culture as a media supplement.  Other applications include use as a protein concentration standard (to determine the quantity of other proteins by comparing an unknown quantity of protein to a known amount of BSA), DNA amplification, immunoassays (such as ELISA’s), blood banking, and bioprocessing. 

BSA is separated from whole blood using a multi-step fractionation process. Dr. Edwin J. Cohn, a researcher at Harvard University, developed the original process in the 1940's.

Dr. Cohn found that the blood proteins could be separated from each other by manipulating the temperature and varying concentrations of an organic solvent.  His process used these two variables to separate human blood plasma into five fractions, of which the fifth contains mostly albumin.  This is why it was called "Fraction V".

Today there are two alternative processes used to extract albumin from plasma; they are Cohn's cold-ethanol process and a heat-shock process. 

What's the difference between "heat-shock" and "Cohn cold-ethanol" prepared BSA?

Most modern fractionation processes for BSA use heat, rather than organic solvents at several key steps.  Ethanolic processes are somewhat dangerous, potentially harmful to the environment and use explosive, highly controlled organic solvents.  

Cold-ethanol fractionation involves adding the solvent to blood plasma at different low temperatures until the albumin is precipitated out.  This process can leave behind impurities and organic compounds that are less than ideal in BSA

Heat-shocked fractionation involves manipulation of temperature and filtration to separate the albumin from the other plasma components.  This generally is a simpler process and yields a product of higher purity.

All bovine serum albumin products are prepared from US sourced serum or plasma and filtered through a 0.2 micron filter before lyophilisation. The products have been tested for protease, nuclease, endotoxin, globulins, cholesterol, fatty acids and heavy metals or bound ions.  All levels have been found to be low or undetectable. All products are high in purity and are negative when tested for active viruses.