Metal interaction chromatography

Metal interaction chromatography is an HPLC technique that can separate many biopolymers because of their differential ability to form complexes with metal ions [1]. It employs a stationary phase with an appropriate metal immobilized via chelating functions bound to the surface. Retention and separation of the sample components occur largely by their interaction with the chelated metal. Although immobilized metal affinity chromatography (IMAC) is a common name for the technique, it is called metal interaction chromatography (MIC) in this book to conform to the nomenclature used for the other interactive chromatographic methods for biopolymer separation by HPLC. 

Janos, P., Separation of some metals as their anionic oxalate complexes by reversed-phase ion-interaction chromatography, /. Chromatogr., 635, 257,1993. 

In 1970s, first application of metal-chelate affinity chromatography which is later named as "immobilized-metal (ion) affinity chromatography (IMAC) was perfomed. Metal-chelate chromatography technique exploits selective interactions and affinity between transition metal immobilized on a solid support (resin) via a metal chelator and amino acid residues which act as electron donors in the protein of interest [25-26]. As well as aromatic and heterocyclic compounds, proteins such as histidine, tyrosine, tyriptophane and phenylalanine posses affinity to transition metals which form complexes with compounds rich in electrons [25,27]. 

Rottmann, L. and Heumann, K.G. (1994) Determination of heavy metal interactions with dissolved organic materials in natural aquatic systems by coupling a high-performance liquid chromatography system with an inductively coupled plasma mass spectrometer. Anal. Chem., 66, 3709—3715. 

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