The protein may have denatured, but try diluting it to as low a concentration as practicable in a neutral buffer containing some salt (e.g. tris-buffered saline) and mixing it gently for a day. You could also try adding gradually increasing concentrations of a denaturant such as urea (1M, 2M, etc.) that can easily be removed later by dialysis. BSA has a lot of disulfide bonds, so its tertiary structure may be fairly stable to urea, whereas the clumps may be disrupted.

Hello there. From what I have understood, I must filter the BSA medium before actually using it. For your information, I apply BSA as a blocking medium for western blotting. To ensure that there isn't any clots in BSA, use a syringe and a Whatman syringe filters (containing polyethersulfone membrane, pore size 0.2 um, diameter 25 mm) and just flush the BSA from the clots. How bad are the 'thick viscous clots'? Do you think you can suck into the syringe I mentioned?

Thank you very much for your answers dear Adam and Nurul

Dear Adam Sir

Am afraid I dont have the membrane for dialysis but the dilution step looks feasible to me i will try it and get back to you with the outcome. i will also look forward to do dialysis taking the help from those who has it.

Dear Nurul

I dont think the thick viscous clots will pass through the syringe or membrane they are too big and if i filter major amount of BSA there in the form of clots may be lost which was not of my interest can you suggest me to improve the use of membrane to get major quantity of denatured BSA.

I am thinking to dilute it using TBS and then filter it through membrane which may help in recovering good amount.