Co-NTA-Agarose for His-tagged proteins

NTA-Agarose consists of the tetradentate chelating agent, nitrilotriacetic acid (NTA), covalently coupled agarose beads, and is loaded with Co2+ ions. In processing recombinant fusion proteins from eukaryotes or in the case of special protein complexes, Genaxxon Co-NTA Agarose should always be used offering the possibility of higher protein purity levels. Both metal ions feature differing spatial properties and electronic binding potentials. While Co2+ binds only domains adjacent to residual histidine and is thus highly selective for 6×histidine-tagged fusion proteins, Ni2+ ions are less specific and can bind residual histidine outside the polyhistidine tag, which may result in higher contamination with foreign proteins. The unique production process yields a Co-NTA Agarose that exhibits a higher protein binding capacity than that of leading competitor products. Genaxxon Co-NTA Agarose is very robust in the presence of DTT and EDTA. In a stability test, Genaxxon Co-NTA Agarose was exposed to increasing concentrations of DTT or EDTA for 1h. Thereafter, the resins were used to purify E. coli-expressed GFP-His in gravity columns. The binding capacity of the resin decreased in the presence of both DTT and EDTA but the decay rate was shallow. Genaxxon NTA Agarose is supplied as a 50% buffered suspension in 20% Ethanol.