Cu-NTA is a term that refers to a copper ion that has been coupled Nitrilotriacetic acid (NTA). Cu-NTA can then be coupled to agarose or magnetic beads for Immobilized Metal Chelate Affinity Chromatography, short IMAC. This is a purification method for two purposes.
- The purification of his tagged proteins
- The enrichment of copper binding proteins
Cube Biotech offers multiple different Cu-NTA based products for your specific assay.
Overview of Cube Biotech's Cu-NTA products for protein purification.
|Usage ||Specific binding and purification of 6x his-tagged proteins |
|Specifity ||Affinity to His-tagged proteins and copper-binding proteins |
|Bead size || |
- 40 µm (agarose resin)
- 30 µm (magnetic beads)
|Binding capacity ||Depending on the application |
|Metal Ion capacity ||>12 µeqv Zn2+/mL. |
|Chelator stability ||Stable in buffer containing 10 mM DTT and 1 mM EDTA |
|Bead Ligand ||Cu-NTA |
Cu-NTA products by Cube Biotech were successfully used in the following publications:
|HrpII ||2017 || Bauer W.S., Richardson K.A., Adams N.M., Ricks K.M., Gasperino D.J., Ghionea S.J., Rosen M., Nichols K.P., Weigl B.H., Haselton F.R., Wright D.W., 1 ||Cu-NTA MagBeads |
|2021 || Miyagi M., Tanaka K., Watanabe S., Kondo J., Kishimoto T.2 ||Cu-NTA MagBeads |
Different metal ions confer different binding affinity and specificity
Depending on the chelating metal ion the results of a His tag protein purification may change. The coupled metal ion influences the balance between protein affinity to the His tagged protein and the specificity of the purification. Copper as the chelating ion is the choice with the highest affinity. Using Copper-NTA will lead to the highest protein yield.
Fig. 1: Affinity and specificity of metal ions commonly used for IMAC. Loading an IMAC resin with different metal ions can adjust the affinity and specificity to optimize the purity and yield of a purified protein.