TEV Protease contains a polyhistidine tag at its N-terminus and can be removed from the reaction by immobilized metal affinity chromatography, such as NEBExpress Ni-NTA Magnetic Beads (NEB #S1423), NEBExpress Ni Spin Columns (NEB #S1427), or NEBExpress Ni Resin (NEB #S1428). The Ni-NTA Magnetic Beads will require dialysis to remove the DTT present in the TEV Protease Reaction Buffer, whereas TEV Protease digests can be directly loaded onto NEBExpress Ni Spin Columns or NEBExpress Ni Resin, since these two resin formats are chemically resistant to DTT.