High performance liquid affinity chromatography (HPLAC) is a powerful method for purification and analysis of biological compounds. It combines the speed and the efficiency of high performance chromatography with the selectivity of affinity chromatography methods. The selectivity depends, first, on the nature of the ligand used; this latter must exhibit a specific binding affinity towards the product to purify; second, it depends on adsorption and desorption processus that improve, or not, the protein affinity for the ligand.