Affinity Chromatography (AC)
Affinity Chromatography (AC) separates molecules based on the reversible interaction between target protein and the specific ligand attached to a chromatography matrix. The interaction can be specific (such as antibodies binding to protein A or protein G), or nonspecific (e.g., a histidine-tagged protein binding to metal ions).
Many other types of biological interactions can be utilized in AC including enzyme-substrate, protein-protein, or nucleic acid-protein interactions. In AC, the sample is applied under conditions that favor specific binding to the ligand. Elution is performed specifically, using a competitive ligand, or non-specifically, by changing the pH, ionic strength, or polarity. The high selectivity of AC enables many separations to be achieved with high purity in a single step. When higher purity is required, one or more additional purification steps may be required. For example, gel filtration (GF) can be used as a final polishing step.
We offer a wide range of affinity media for purification of affinity-tagged proteins, antibodies, or specific classes of molecules. AC is also used to remove specific contaminants. In addition to ready-to-use affinity media, we offer preactivated chromatography matrices for convenient immobilization of your ligand of choice.