Immobilized metal ion affinity chromatography (IMAC) is the most widely used purification technique. It is based on the interaction between certain protein residues (histidines, cysteines), with transition metal cations, forming chelates. These transition metal ions bind to the agarose beads through a chemical reaction, giving the agarose an activation state.
Nitrilotriacetic acid (NTA)-crosslinked-agarose resin consists of NTA groups covalently immobilized on agarose beads by stable ether linkages via a spacer arm.
NTA is a tetradentate chelating agent forms octahedral coordination complex with divalent transition metal cations (Ni2 ) along with two water molecules occupied in cis manner. This ready to use resin, after loading with a divalent transition metal ion (Ni2 ) is ideal for rapid purifications of His-tagged proteins. In comparison with other chelating resins such as iminodiacetic acid (IDA)-agarose, the NTA has two sites (cis) available for the interaction with imidazole of His-tagged proteins, instead of the three in IDA, and so have lesser probability of nonspecific binding. NTA resins are usually more easily regenerated, allowing a better elution of the fused proteins bound with smaller concentrations of imidazole.
Product is supplied as 50% suspension of Ni-NTA Agarose resin in 20% aqueous ethanol; the settled bead volume
was measured in ml when supplied.
> Under optimum condition, 1.0 ml of Ni-NTA Agarose Bead can purify up to 50 mg of His-tagged protein.
> BBL Ni-NTA Agarose Bead can withstand autoclaving at 120°C for 20 min without any significant loss of binding efficiency.
BEAD GEOMETRY & SIZE: Spherical, ∼ 50 – 150 μm diameter
CROSS-LINKED : Yes
BEAD AGAROSE % : 4%
ACTIVATING GROUP : Epoxy
MATRIX STABILITY : Stable in all commonly used reagents
STORAGE SOLUTION : 20% Ethanol
STORAGE TEMPERATURE: 4°C to 8°C. DO NOT FREEZE