Bovine Serum Albumin

General description
Bovine serum albumin (BSA) is a 66 kDa protein consisting of three domains with two subdomains under each. It is a α-helical, globular and non-glycosylated protein.[1] It belongs to the serum albumins family. It has 17-disulfide bonds.[2] Albumin is the most abundant plasma protein in humans.[3] Application
Bovine Serum Albumin has been used:
as a component in chromatin immunoprecipitation (ChIP IP) buffer[4] in combination with electrospun polystyrene (ESPS) fiber mats for fluorescence microscopy[5] as a component of blocking solution and immobilzation studies[5] as a component in phosphate buffer saline (PBS)[6]

Biochem/physiol Actions
Bovine Serum Albumin (BSA) is a transporter for drugs, hormones and fatty acids.[1] High levels of albumin is associated with dehydration. Albumin turnover is seen in infants with iron deficiency anemia.[3] Certain conformational and primary-sequence epitopes of BSA are suspected allergens in human beef and milk allergies.
Preparation Note
Derived from New Zealand source serum
Prepared using heat shock fractionation
Serum albumin may be referred to as Fraction V. This naming convention is taken from the original Cohn method of fractionating serum proteins using cold ethanol precipitation. Serum albumin was found in the fifth ethanol fraction using Cohn′s method. Since then, the term “Fraction V” has been used by some to describe serum albumin regardless of the method of preparation. Others have used this term to describe serum albumin purified by ethanol fractionation methods that have been highly modified since the original Cohn method was described. Sigma-Aldrich manufactures and distributes serum albumins purified from a variety of primary methods including the true Cohn fractionation method, modified ethanol fractionation methods, heat shock and chromatography. Additional purification steps may include crystallization or charcoal filtration.