in vivo method ex vivo method electron paramagnetic resonance spectroscopy 2020-05-22T11:14:53Z A method for studying materials with unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but it is electron spins that are excited instead of the spins of atomic nuclei. EPR spectroscopy ESR spectroscopy MMO:0000710 electron spin resonance spectroscopy measurement_method_ontology slaulede