pI for one protein is at pH 4 Which pH should contain purif

pI for one protein is at pH = 4. Which pH should contain purification buffer to retain this

protein on a cation-exchange column?

Solution

pI for that particular protein is at pH= 4. So in pH 4 the protein moves neither to anode nor to cathode. So we must choose a buffer that have pH<4. In such a pH <4 the protein will have a net negative charge.and it will easily attract towards negatively charged beads. So , we have to keep pH <4 of purification buffer for the particular case..