Biotin-X IDA

Immobilized metal affinity chromatography (IMAC) is a popular method for protein purification, particularly for recombinant proteins fused to a polyhistidine-tag. Transition metal ions immobilized to a matrix through a chelating ligand interact with the polyhistidine-tag, effectively sequestering the fused protein from a sample. Nitrilotriacetic acid (NTA) and iminodiacetic acid (IDA) are two such ligands commonly used in commercially available resins. AAT Bioquest offer a variety of NTA building blocks for developing either NTA-based purification and detection. IDA is complimentary to NTA. The tridentate IDA ligand requires a lower imidazole concentration to elute protein than the tetradentate NTA. IDA is a smaller molecule which can be coupled to the matrix at a higher density resulting in a higher metal loading capacity. Biotin IDA is a bifunctional reagent that can be used to detect histidine-tagged proteins immobilized. Biotin IDA can be removed from the histidine-tagged protein at pH 4.8, allowing the blot to be reanalyzed with another probe.