Reactive oxygen species (ROS)

Free radicals are chemical species of high oxidative potential that can damage the human body on a cellular level. They can be detected by ESR applying a fast, simple and sensitive measurement.

Analysis for peroxide-radical production by using ESR.
(A) Representative ESR spectra.
(B) Grouped data presented as mean
(Cai et al. 2005)


Human beings and animals exhale nitric oxdie (NO), which is formed in the nasal cavities and lungs. A pathological status such as inflammation is expressed by higher NO output. Also, the inner human body as well as single-cell organisms are confronted with peroxyl- and hydroxyl-radicals, so-called oxidative stress.


To explore causes and production mechanisms of these species, ESR is applied to detect these oxygen-derived radicals inside living tissue. Today's Life Science is driven by the search for a fundamental understanding of life's degrading and renewing processes. With the help of the MS 5000, this can be found.

Spin trapping of nitric oxide

  • "catching" short-lived radicals for specific measurement

  • spin traps: NO cheletropic traps, colloid Fe(II)(DETC)2

Fenton reaction

While observing free radicals in human blood, a peculiar formation mechanism is revealed.

Diseases related to oxidative stress

pulmonary hypertension, diabetes, cancer