Bovine Serum Albumin: What it is and Why it’s Used

Bovine Serum Albumin, also referred to as “BSA,” is a serum albumin protein that has multiple biochemical applications.  To start with, let’s look at where BSA comes from. BSA can be produced through a purification of bovine, or cow, blood.  Due to the size of the cattle industry, bovine blood is a readily available resource.

To expand more on the process of how Bovine Serum albumin is made, there are today two different processes typically used.  The original process is known as the cold-ethanol process or “Fraction V” method, and was developed by Dr. Edwin J. Cohn in the 1940’s.  The other process is more modern and known as the heat-shock process.  The primary difference between these two methods for bovine serum albumin creation is that the heat-shock process uses heat, rather than organic solvents for a number of steps.  The reason for this is that the processes using ethanol can be dangerous due to their use of potentially explosive solvents as well as environmental impact concerns.

Now what are some of the applications of or uses for bovine serum albumin?  BSA is often used in cell culture media.  Cell culture media is a growth medium or culture medium typically in the form of a gel or liquid that is used to support the growth of microorganisms.  When trying to grow animal cells outside of the body, serum proteins are required in order to facilitate that growth.  Bovine serum albumin is well known for its high stability, which makes it an ideal component.  BSA also is used in “restriction digest,” which is a process in molecular biology that prepares DNA for analysis and processing.

So there are a lot of useful applications for bovine serum albumin.  It’s quite interesting to see how science can find so many uses for bovine blood, a commonly available byproduct of slaughterhouses.