FAQ: Why is imidazole not necessary in the lysis/binding buffer? Why does the wash buffer contain only 5mM imidazole?

NEBExpress™ Ni Spin Columns utilize a highly selective, proprietary resin that unlike conventional Ni-NTA, requires less imidazole in the purification.  Nickel ions are immobilized on the matrix surface via a proprietary ligand that is highly uniform and stable and offers excellent resistance to a wide range of chemicals, including NaOH, EDTA, DTT and β-ME.