sample salt concentration - (Jan/06/2008 )

how do u know the NaCl concentration in your sample? i have sample (blood serum) i want to recover the albumin from the sample preparing to run it on SDS-PAGE.. but in the protocol for albumin recovery procedure they ask to perform it on low NaCl concnetration how do i know the original concentration..and what is the best way to control it?

thanks

You can assume it to be physiological salt concentration at ~150 mM NaCl.

dilute it with 2 volume of 10 mM Tris-HCl buffer or the buffer that is recommeneded. you can dialysis against 50 mM NaCl-buffer if you dont want it to be too diluted.