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Bovine Serum Albumin

heat shock fraction, suitable for RIA, pH 5.2, ≥96%

Albumin bovine serum, Bovine albumin, BSA
CAS Number:
EC Number:
MDL number:

Quality Level

biological source





lyophilized powder


suitable for RIA

mol wt

~66 kDa

purified by

heat shock fractionation


poly bottle of


USA origin


blood typing: suitable






water: soluble (40 mg/ml)


suitable for insulin RIA procedures

UniProt accession no.

storage temp.


Gene Information

bovine ... ALB(280717)

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General description

Bovine serum albumin (BSA) is 66 kDa protein consisting of three domains with two subdomains under each. It is α-helical globular and a non-glycosylated protein.


Bovine Serum Albumin has been used:
  • as a blocking agent in enzyme linked immunosorbent assay (ELISA)(154)
  • as a component of Dulbecco PBS medium for preantral follicles culture(155)
  • as a component of modified Tris-buffered medium (mTBM) for oocyte insemination(156)


10, 50, 100, 500 g in poly bottle

Biochem/physiol Actions

Bovine Serum Albumin (BSA) is a transporter for drugs, hormones and fatty acids. It is a blocking agent used in enzyme linked immunosorbent assay (ELISA) for preventing non-specific binding of antigens and antibodies to the microtiter plates. The cysteine and tyrosine residues of BSA have high affinity for metal binding.
Certain conformational and primary-sequence epitopes of BSA are suspected allergens in human beef and milk allergies.

Features and Benefits

  • Heat shock fractionated
  • Suitable for radioimmunoassay (RIA)


May yield an insulin blank of up to 0.1 μunit per mg in certain procedures.

Preparation Note

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.

Storage Class Code

11 - Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificate of Analysis

Enter Lot Number to search for Certificate of Analysis (COA).

Certificate of Origin

Enter Lot Number to search for Certificate of Origin (COO).

  1. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  2. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  3. What is the molecular weight of Product A7888, Albumin from bovine serum?

    BSA consists of 583 amino acid residues.  The molecular weight calculated by NIST is 66429.03. It has also been calculated by GPMAW (General Protein Mass Analysis for Windows) as 66429.94.

  4. What does RIA grade mean in the description of Product A7888, Albumin from bovine serum?

    RIA grade means that this product has been shown suitable for radioimmunoassays.

  5. At what concentration is Product A7888, Albumin from bovine serum (BSA), soluble in water?

    We have not established an upper limit of solubility for this product in water.  At 40 mg/mL, an aqueous solution of  this product may light yellow to green and slightly hazy.

  6. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  7. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  8. My question is not addressed here, how can I contact Technical Service for assistance?

    Ask a Scientist here.

Lara Vlietstra et al.
PloS one, 14(6), e0217462-e0217462 (2019-06-07)
To determine if there is an association between sarcopenia, physical function and self-reported fatigue in osteoarthritis (OA) and rheumatoid arthritis (RA). A cross-sectional analysis of measurements from a cohort of 157 participants with OA or RA was performed. The relationship
Shiro Miyake et al.
Journal of pesticide science, 44(3), 156-161 (2019-09-19)
A direct competitive enzyme-linked immunosorbent assay (dc-ELISA) was developed for determination of anilinopyrimidine fungicide mepanipyrim in vegetables. Two derivatives of mepanipyrim and mepanipyrim propanol type metabolite which carried carboxy acid were synthesized and conjugated with keyhole limpet hemocyanin. BALB/c mice
K B Cullberg et al.
Nutrition & diabetes, 4, e113-e113 (2014-03-26)
High levels of free fatty acids (FFA) have been suggested to be one of the underlying mechanisms for adipose tissue (AT) inflammation and dysfunction in obesity. Human AT produces several adipokines including monocyte chemoattractant protein-1 (MCP-1), which are involved in
Enzyme-linked immunosorbent assay (ELISA) and blocking with bovine serum albumin (BSA)?not all BSAs are alike
Xiao Y and Isaacs SN
Journal of Immunological Methods, 384(1-2), 148-151 (2012)
Bovine serum albumin interactions with metal complexes
Topalua T, et al.
Clujul Medical (1957), 87(4), 215-215 (2014)

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