Affinity Purification

Many strategies can be applied to purify proteins; however, a common type of purification is affinity chromatography. This method is often preferred because it can rapidly yield pure recombinant protein in a single chromatography step. In its most typical application, a protein “tag” that has affinity for a specific immobilized substrate is genetically encoded and expressed as a fusion to the target protein. The tagged protein can then be recovered from a complex mixture (such as a cell lysate) by contacting the mixture with a chromatography resin that displays a substrate to which the tag selectively binds. Common tags include polyhistidine (His-tag), maltose binding protein (MBP-tag) and chitin binding domain (CBD-tag). 

NEB offers a variety of purification resins and beads, including nickel spin columns (NEB #S1427), nickel magnetic beads (NEB #S1423) and nickel resin (NEB #S1428) to enable rapid purification of His-tagged proteins. Amylose resins for purification of MBP-tagged proteins are available in a variety formats (standard (NEB #E0821), high flow (NEB #E0822) and magnetic (NEB #E8035), as well as Chitin resin (NEB #S6551) for rapid purification of CBD-tagged proteins