CHROMATOGRAPHIC AND EPR STUDY OF POLY(VINYLIMIDAZOLE) COPPER(II) COMPLEXES SUPPORTED ON SILICA

Cu(II) complexes of poly(1-vinylimidazole) immobilized on silica parti cles have been used as stationary phases for immobilized metal affinit y chromatography of some proteins. Chromatographic data are reported w hich suggest that protein retention depends on the ionic strength in t he column before and during loading with Cu(II). It has been shown by EPR spectroscopy that [Cu(Im)6]2+-type complexes were predominant when Cu(II) binding was performed in pure water. When performed under cond itions of greater ionic strength, lower complexes are probably also fo rmed. Protein retention has been shown to depend on other factors, suc h as the amount of Cu(II) bound to the column and the composition of t he mobile phase.