Albumin is a soluble, monomeric protein has molecular weight of c. 66 kDa. It is primarily as a carrier protein for steroids, fatty acids, and thyroid hormones and plays a role in stabilizing extracellular fluid volume. Serum albumin protein has numerous biochemical applications including ELISAs, immunoblots, and immunohistochemistry. It is also used as a nutrient in cell and microbial culture.