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. BSA belongs to the serum albumins family. It has 17-disulfide bonds.

Bovine Serum Albumin has been used in:

• the washing of the rabbit tissue sections in immunofluorescence microscopy
• incubation of red blood cells (RBC) for flow cytometry analysis
• as a component of Hanks′ balanced salt solution with Ca²⁺ and Mg²⁺ (HBSS++) for eosin-5-maleimide staining and RBC washing in magnetic circular dichroism measurements

BSA的某些构象和初级序列表位是人类对牛肉和牛奶过敏中的可疑过敏原。

Bovine Serum Albumin (BSA) is a transporter for drugs, hormones and fatty acids. It is used as a blocking agent in enzyme linked immunosorbent assay (ELISA) for preventing non-specific binding of antigens and antibodies to the microtiter plates. It is a crucial component of the cell culture media and favors embryonic stem cells (hESC) differentiation. BSA shares structural features with human serum albumin. Its high solubility, low cost and purity and interaction with surfactant is exploited in cosmetic and pharmaceutical industry.

血清白蛋白可能也会被称为Fraction V。该命名惯例取自使用冷乙醇沉淀对血清蛋白进行分级的原始Cohn法。 血清白蛋白可在采用Cohn′法的第五乙醇分级中发现。 从此，有些人便开始使用“Fraction V”这一术语来描述血清白蛋白，无论使用的是什么制备方法。 也有人在使用该术语来描述通过乙醇分级方法而纯化得到血清白蛋白，而这种方法是相对于原始的Cohn法一直在得到高度的改良。Sigma-Aldrich生产和分销从各种主要方法纯化得到的血清白蛋白，包括真正的Cohn分级法、改良的乙醇分级方法、热休克和色谱法。 更多的纯化步骤包括结晶或木炭过滤。

通常称为 Cohn fraction V；本品采用改进的 Cohn 氏冷乙醇分级分离法制备。