Electron paramagnetic resonance imaging
Citation, DOI, disclosures and article data
At the time the article was created Bálint Botz had no recorded disclosures.View Bálint Botz's current disclosures
At the time the article was last revised Daniel J Bell had no recorded disclosures.View Daniel J Bell's current disclosures
Electron paramagnetic resonance imaging (EPR) and spectroscopy is a preclinical imaging modality with potential to be translated into a clinical imaging technique in the future. In brief, electron paramagnetic resonance imaging allows detection and quantification of free radical molecules with unpaired electrons, thus allowing measurement of free radical production and redox status in living subjects with manifold practical implications (e.g. assessment of tumor hypoxia and viability). As of 2021, no clinical EPR scanners are yet available.
Electron paramagnetic resonance imaging is similar to nuclear magnetic resonance (NMR), the key difference is that during electron paramagnetic resonance imaging the electron spins are excited by a magnetic assembly, instead of the spins of atomic nuclei.
Most biologically-relevant free radicals, such as superoxide, hydroxyl and nitric oxide free radicals contain unpaired electrons which may undergo excitation 1. Since the concentration and half-life of these substances is very low, their direct detection has proved to be challenging. Therefore, efforts have been made to facilitate their detection by using redox-sensitive paramagnetic "spin trap" imaging probes 2,3.
- 1. In Vivo Electron Paramagnetic Resonance: Radical Concepts for Translation to the Clinical Setting. (2018) Antioxidants & Redox Signaling. 28 (15): 1341-1344. doi:10.1089/ars.2017.7472 - Pubmed
- 2. Fujii, Hirotada G., Emoto, Miho C., Sato-Akaba, Hideo. Brain Redox Imaging Using In Vivo Electron Paramagnetic Resonance Imaging and Nitroxide Imaging Probes. (2019) Magnetochemistry. 5 (1): 11. doi:10.3390/magnetochemistry5010011
- 3. Swartz HM, Williams BB, Zaki BI, Hartford AC, Jarvis LA, Chen EY, Comi RJ, Ernstoff MS, Hou H, Khan N, Swarts SG, Flood AB, Kuppusamy P. Clinical EPR: unique opportunities and some challenges. (2014) Academic radiology. 21 (2): 197-206. doi:10.1016/j.acra.2013.10.011 - Pubmed