TSKgel Chelate-5PW utilizes the tendency of iminodiacetic acid (IDA) to form a complex with metal ions, such as Zn²⁺, Ni²⁺ and Cu²⁺. The column is loaded with divalent metal ions by chelation.  Peptides and proteins containing histidine residues will normally adsorb to these chelated ions at neutral pH. The retained compounds can be eluted with buffer containing imidazole or glycine. The key to making successful use of this retention mechanism is the proper selection of metal ions for chelation and the elution buffer to desorb the analytes. In general, Cu²⁺, interacts better with proteins; however, resolution is usually enhanced with Zn²⁺. A gradient mobile phase containing increasing imidazole or glycine concentrations is used to elute the retained compounds. Alternatively, a decreasing pH gradient can be used for elution purposes as well.

Applications include: immunoglobulins, transferrin, lectins, milk proteins, membrane proteins and peptides.