Rigose PlasmidPure is a kind of thiophilic aromatic adsorption chromatography resins which use 2-mercaptopyridine as their ligands. And these resins have the selectivity that allows supercoiled covalently closed circular forms of plasmid DNA to be separated from open circular forms. The resins were designed for purification and obtaining of high-quality supercoiled DNA which are used for gene therapy and DNA vaccine applications.