Affinity chromatography

Affinity chromatography (also called bioaffinity chromatography) is a method to filter a specific molecule out of a solution. An affinity absorbent which consists of an immobilized molecule which can bond to the target molecule is used to immobilize the target molecule.

The process
1. The affinity absorbent is added to the solution.

2. The molecules that bond bind get washed out.

3. The affinity absorbed get separated from the target molecule by either changing the pH value of the solution, ionic strength or polarity.

There are a variety of affinity absorbents which work for different molecules. It is important to select one that doesn't bond to other molecules in the solution.