<P> BSA has numerous biochemical applications including ELISAs ( Enzyme - Linked Immunosorbent Assay ) , immunoblots , and immunohistochemistry . Because BSA is a small , stable , moderately non-reactive protein , it is often used as a blocker in immunohistochemistry . During immunohistochemistry , which is the process that uses antibodies to identify antigens in cells , tissue sections are often incubated with BSA blockers to bind nonspecific binding sites . This binding of BSA to nonspecific binding sites increases the chance that the antibodies will bind only to the antigens of interest . The BSA blocker improves sensitivity by decreasing background noise as the sites are covered with the moderately non-reactive protein . During this process , minimization of nonspecific binding of antibodies is essential in order to acquire the highest signal to noise ratio . BSA is also used as a nutrient in cell and microbial culture . In restriction digests , BSA is used to stabilize some enzymes during the digestion of DNA and to prevent adhesion of the enzyme to reaction tubes , pipet tips , and other vessels . This protein does not affect other enzymes that do not need it for stabilization . BSA is also commonly used to determine the quantity of other proteins , by comparing an unknown quantity of protein to known amounts of BSA ( see Bradford protein assay ) . BSA is used because of its ability to increase signal in assays , its lack of effect in many biochemical reactions , and its low cost , since large quantities of it can be readily purified from bovine blood , a byproduct of the cattle industry . </P>
why we use bsa as standard for protein estimation
ability to increase signal in assays lack of effect in many biochemical reactions low cost