BSA by HPLC

[MK]

Hi,

Can I determine Bovine Serum Albumin (BSA) by HPLC? I need to go as low as 40 ng/ml.

many thanks
MK

[HW Mueller]

Determine what about BSA?

[MK]

Residual quantity of BSA from a liquid formulated bio drug product

thanks
MK

[HW Mueller]

Since BSA is a whole array of different molecules you would have a hard time doing this or comparing it to other literature "BSA concentrations". Maybe a coomassie blue test or any number of other tests would be more appropriate. (Havn´t done this for some time, but seem to remember that Pierce has a bunch of things for this, maybe looking for "total protein determination" in the internet will overwhelm you). If your analyte is a peptide or protein this wouldn´t work, of course. A size exclusion column may bunch the BSA pretty much together.... away from your analyte, but you still may have a problem to compare this to the lit., if needed. Ultrafiltration + a total protein test also comes to mind.

[Rande]

For residual Bio-Process Contaminants, HPLC is not the "right tool for the job".

1) it is not sensitive enough
2) you can not be sure you could detect or identify BSA subunits, that could still be immunoreactive.

Most people use some type of ELISA for Process Residuals (BSA, Serum Proteins, Insulin, Host Cell Protein, residual Protein A, etc.)

Cygnus Technologies sells ELISA Kits for all of these. I have had good luck with them, and I feel they are well accepted in the industry.

Their BSA kit has a limit of detection of <250pg/mL.

see : http://www.cygnustechnologies.com/index.html

Good Luck and Have Fun,

[HW Mueller]

MK, from the answers so far you can surmise that this will be an approximation no matter which "accepted" method you do. It´s not as bad as it sounds as long as this is not forgotten.