Immobilized enzyme electron spin resonance (IE-ESR) is an electron spin resonance technique used to detect short lived radicals generated from enzyme reactions. This method is an alternative to the more commonly used continuous-flow or fast-flow ESR method.
Development
The IE-ESR method was developed in the laboratory of Roanld P. Mason at the National Institute of Environmental Health Sciences/National Institutes of Health (NIEHS/NIH) by post doctoral fellows Bradley E. Sturgeon and Yeong-Renn Chen. The IE-ESR method was first used to detect the tyrosine iminoxyl radical. This radical is the 1-electron oxidized form of nitrosotyrosine that was a results of the tyrosyl radical reacting with nitric oxide. A second publication using the IE-ESR method showed the increase in peroxidase activity of cytochrome c as a result of HOCl treatment. The complete paper describing the method was published in 2003.