A8531 Sigma

Bovine Serum Albumin

pH <5.0, powder

Synonym: Albumin bovine serum, BSA, Bovine albumin



Related Categories Albumin, Albumins by Application, Biochemicals and Reagents, Bovine Serum Albumins, Ethanol Fractionated,
form   powder
mol wt   mol wt ~66 kDa
  mol wt ~66,000
packaging   vial of 50 mg
impurities   ~0.3% dithiothreitol
pH   <5.0
suitability   suitable for (Suitable for use as a gel filtration marker)
storage temp.   −20°C


Preparation Note

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.


Albumin from bovine serum was used:
• for blocking of nonspecific immunoglobulin during immunohistochemical reactions.
• to coat microplates for blocking non-specific binding during I-ELISA (Indirect Enzyme-linked Immunosorbent Assay)
• as molecular mass standard in analytical gel filtration chromatography for Superdex® 75 10/300 GL gel filtration column.
• For measuring fluorescence for PR1 (phytofluor red 1) by using Fluorescence correlation spectroscopy (FCS)
• As a reference mixture along with horse Mb in Size Exclusion Chromatography
It can be used as a gel filtration molecular weight marker. It can be used in medical studies to quantify binding capacity and adsorption rate of protein enrichment and separation medium critical in proteomic research.

Gel filtration molecular weight marker

Biochem/physiol Actions

Bovine serum albumin also refers as BSA or Fraction V is a protein isolated from cows. BSA can block vacant binding sites in enzyme-linked immunosorbent assay (ELISA) in both poly-l-lysine (PLL)-treated and non-treated microwells. It can also triggers the insulin dependent diabetes mellitus.

Certain conformational and primary-sequence epitopes of BSA are suspected allergens in human beef and milk allergies.

Legal Information

Superdex is a registered trademark of GE Healthcare

Protocols & Applications

Select the right albumin for your application with the Albumin Selection Guide

Price and Availability

Safety & Documentation

Safety Information

NONH for all modes of transport
WGK Germany 
Protocols & Articles


Gel Filtration Markers Kit for Protein Molecular Weights 12,000-200,000 Da

Gel filtration chromatography is an established method for determining the size and molecular mass of proteins. Fractionation is based on the diffusion of molecules into the pores of the resin. Large...
Keywords: Chromatography, Diffusion, Filtration, Fractionation, High performance liquid chromatography, Size-exclusion chromatography

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