er..... what do you want to ask?  BSA solution for blocking? 20 mg/10 mL, you just need to use a 20 mL voluetric flask and dilute 20mg BSA powder with dd water to volume. is it what you want?

but my question is that if I take 20mg BSA into 10mL PBS in conical tube and put  in refrigerator until proper melting,is this right way to make BSA (20mg/10mL)?

Hello Abdul,

I would suggest that you start of with a volume slightly less than your final volume. Consider taking 9 ml of your liquid (this could be PBS, Tween-PBS, MilliQ, ddH2O, etc) and dissolving the required mass of BSA in this. You can dissolve at 4C, but we often did it at room temperature for smaller volumes. Try not to agitate the liquid too much and stir at a low speed of you choose to use a magnetic stirrer. The solution will foam otherwise. After the BSA is dissolved, top up the liquid to the required volume, in your case, 10 ml. A small volumetric flask might be the best for this volume.

If you just simply add 20 mg of BSA to 10 ml of PBS your concentration might be slightly out due to the addition of the solute to the solvent.

Hope it all makes sense.