Choosing a country will allow you to access local content and enable you to shop in your local currency.
Didn’t find your country? Please proceed to our International Site.
Applications & Technologies
We're Sorry.
/Technology Insights/Chromatography/Affinity Chromatography (AC)/affinity-chromatography-465x262.jpg)
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.
|
Today, most lab-scale purifications are performed with affinity-tagged proteins, such as the purification of histidine-tagged proteins using IMAC, also known as metal chelate affinity chromatography. In this technique, the medium is first charged with a divalent metal ion (e.g., Ni2+, Cu2+ , Zn2+, or CO2+), which is immobilized to the medium via a chelating ligand. When sample is applied, proteins containing histidine, cysteine, and tryptophan residues bind the immobilized metal ions. Bound protein can be eluted by competitive elution with imidazole, for example, or by lowering the pH. Since many proteins have intrinsic histidine and/or cysteine amino acid residues, some nonspecific binding to the IMAC media can occur. Therefore, it is often necessary to optimize binding, wash, and elution conditions by varying the concentration of imidazole in these solutions. Increasing the concentration of imidazole in the binding and wash buffers generally decreases nonspecific binding, whereas lower concentrations give stronger affinity interaction. The key is finding the right balance. Find out more about our precharged and uncharged IMAC Media. Choose from bulk media, prefilled 96-well filter plates, and several prepacked column formats including HiTrap columns and spin columns. |
/Technology Insights/Chromatography/Affinity Chromatography (AC)/IMAC.jpg)
|
.png)
Our products for affinity chromatography are used at all scales, from lab-scale work to biopharmaceutical manufacturing.
© 2012 General Electric Company doing business as GE Healthcare
We've detected that you're using an unsupported browser.You may continue browsing, but for the best experience, please use Mozilla Firefox (v.30+), Google Chrome (v.35+) or Internet Explorer (v.11+).
This website would like to place cookies on your computer to help us serve you better. To understand how we use cookies, please view our privacy policy.
