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pH and Ni-column? - (Apr/21/2008 )

How does pH effect the Ni-NTA column? Just wondering which pH will reduce other proteins from binding to the column? Thanks

-olifu02-

Lower pH will reduce binding to the Ni2+ column. In fact you can even elute your protein off the column using low pH if your protein can handle it. However I am going to guess that you want to play with the pH to get your elutions more pure. In that case I highly recommend raising the salt concentration in your binding buffer (Try 400mM NaCl for starters), using less resin (binding capacity of Ni-NTA = ~10mg/ml), or trying Co2+ beads such as Talon resin (especially if you are having problems with HSP70)

Good Luck

-drewaight-