Affinity chromatography using metal ions

Abstract

A process for the affinity chromatographic separation of at least one biological or related substance from a mixture wherein the at least one biological or related substance is bound to a binding material, having a ligand containing at least one of the groups anthraquinone, phthalocyanine or aromatic azo, in the presence of at least one metal ion selected from the group Ca.sup.2+, Sr.sup.2+, Ba.sup.2+, Al.sup.3+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+ or Zn.sup.2+. The preferred metal ions are Co.sup.2+, Ni.sup.2+ and Zn.sup.2+, with Zn.sup.2+ being particularly preferred. The ligand may be linked directly to the matrix or via a spacer arm. The process may be performed at atmospheric pressure or under pressure, especially high pressure (100-3500 psi). The nature of the contact, washing and eluting solutions depends on the substance to be separated. Generally the contact solution is made up of the substance to be separated and a metal salt dissolved in a buffer solution, while the washing solution comprises the same metal salt dissolved in the same buffer. The eluting solution, may be a buffer solution, either alone or containing a chelating agent or it may be an alkali metal salt or a specific desorbing agent. Alternatively the eluting solution may be a mixture of two or more of these solutions or two or more of these solutions used consecutively.