About Ion chromatography
Ion chromatography (or ion-exchange chromatography) basically separates the molecule into its ions and polar molecules based on their affinity to the ion exchanger. Most preferably it works any kind of charged molecule, including large proteins, small nucleotides, and amino acids. The two types of ion chromatography are anion-exchange and cation-exchange. It is often used in quality control, protein purification and water analysis.