EPR at 80: Carotenoid Radical Cation Detection

Abstract Electron Paramagnetic Resonance (EPR) has proven to be a powerful research tool in the study of carotenoid radicals providing detailed information on their structure, stability, and biological functions. Previously published simultaneous electrochemical and EPR ( SEEPR) and high-field/high-frequency (HFEPR) experiments in vitro performed by Kispert’s group and in collaboration with National High Magnetic Field Laboratory (NHMFL) for the HFEPR measurements, were extremely helpful in elucidating the structure of the carotenoid radical cation and obtaining EPR parameters for carotenoids that were further used in the literature for comparison with parameters obtained for in vivo experiments.