In principle, yes, but you may not be able to use it if there are detergents in your cell lysis buffer. For example SDS would interefere with the assay at relatively low concentrations.

You could do a simple check by doing a calibration graph using the lysis buffer to make the BSA dilutions, then adding to the assay as normal. Is always best to dilute the standard in the same buffer as the sample to check for interference or effects on linearity.

BSA is normally used as the standard in most protein assays. You just have to be aware that you are measuring protein concentration in BSA equivalents.

We used to use the Lowry and Bradford assays but now routinely use the BCA assay as it is less prone to interference and relatively sensitive, and the reagent goes for the peptide backbone rather than specific groups as in the case of the other assays. However, we always dilute the standard in the same buffer as the sample for the calibration graph.

I hope this helps.

Best regards

Alan Hargreaves

In principle, yes, but you may not be able to use it if there are detergents in your cell lysis buffer. For example SDS would interefere with the assay at relatively low concentrations.

You could do a simple check by doing a calibration graph using the lysis buffer to make the BSA dilutions, then adding to the assay as normal. Is always best to dilute the standard in the same buffer as the sample to check for interference or effects on linearity.

BSA is normally used as the standard in most protein assays. You just have to be aware that you are measuring protein concentration in BSA equivalents.

We used to use the Lowry and Bradford assays but now routinely use the BCA assay as it is less prone to interference and relatively sensitive, and the reagent goes for the peptide backbone rather than specific groups as in the case of the other assays. However, we always dilute the standard in the same buffer as the sample for the calibration graph.

I hope this helps.

Best regards

Alan Hargreaves

Thank you very much.

I've just managed with my measurements. In our case cell-lysate was get by freeze/thaw, so there were no detergents. Though the information about detergents influence was new for me. I do believe it will help me in future experiments as well as a recommendation about BCA assay.

Thank for your advices.

Hello!!!

I recommend this paper about common problems with protein determination for take into account some tips that improve de quality of determination...

Besides, you can precipitate with inorganic salts or organic solvents!!

The Bradford assay can be use when testing samples have not high consentration (not more 50 mkg) of protein.

can we use same buffer to perform bradford and lowery assays

Samples and standards should always be diluted in the same buffer and the same volumes added in the assay to minimise risks of interferance.

However, before assaying samples that may be available in very limited amounts, you should always run a 'normal' assay in parallel with a set of standards diluted with the sample buffer to ensure that it doesnt  affect the absorbance readings or that at least it gives good linearity