BSA in protein for stabilization

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Somacard
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BSA in protein for stabilization

 I understand BSA as a blocking agent and why it is commonly used, cheap and readily available.  In my lab I have been mixing my protein with BSA to increase stability while running the assay.  The protein in question is from a lyophilzed powder and reconstituted with water and glycerol for long term storage (-70C).  When prepared in its normal buffer solution the response of the protein, immunoblotting, is weaker and less consistent than when prepared in 1% BSA to buffer solution.  I have found other articles referring to BSA being used in this method as a "common industry standard," but does anyone know the mechanism by which this happens?  

g a
g a's picture
Dear Somcard

Dear Somcard

Diluted protein solutions (< 1 mg/ml) are prone to inactivation and loss as a result of low-level binding to the storage vessel. Therefore, it is common practice to add “carrier” or “filler” protein, such as purified bovine serum albumin (BSA) to 1-5 mg/ml (0.1-0.5%), to dilute protein solutions to protect against such degradation and loss. Dilute protein solutions (< 1 mg/ml) are more prone to inactivation and loss as a result of low-level binding to the storage vessel. Therefore, it is common practice to add “carrier” or “filler” protein, such as purified bovine serum albumin (BSA) to 1-5 mg/ml (0.1-0.5%), to dilute protein solutions to protect against such degradation and loss. 

All the Best

 

RAMYA12345
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Sir,

Sir,

I have a problem regarding the stability of BSA. Usually we dissolve 0.5% BSA  solution (dissolved in 0.05M Phosphate buffer stored at -20 C) along with the protein in the asay to prevent the degradation of protein because the incubation time is overnight. My question is whether the BSA solution that has been stored at -20 is losing its stability due to repeated freezing and thawing. Because it is found that the standards are losing its potency. Can you provide me the details on stability of the BSA solution?

g a
g a's picture
 Dear Ramyasri

 Dear Ramyasri

Repeated freeze thaw cycles are the reasons for loss of protein activity as it leads to breakdown of proteins. Try aliquoting it in small volumes as are required for your experiments and avoid multiple freeze thaw cycles.

RAMYA12345
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T5hanks a lot for ur reply

T5hanks a lot for ur reply sir