A novel approach to the analysis of spin-trapped free radicals using dimethyl sulfoxide and Gas Chromatography – Mass Spectrometry (GC-MS) with both solvent extraction and headspace solid phase microextraction (HS-SPME)

Mishra, SS; Manzoor, K; Zafar, M; Podmore, ID

Abstract

In this study, we have utilized a novel strategy based upon the use of dimethyl sulfoxide (DMSO) and gas chromatography-mass spectrometry (GC-MS)for the detectionand identification ofspin-trapped free radicals. Hydroxymethyl (.CH2OH) radicals, generated by Fenton-type chemistry,have been trapped byN-tert-butyl-α-phenylnitrone (PBN) or one of its derivatives in the presence of DMSOto form a1,3-diadduct[PBN-(CH2OH)(CH3)],which may be detected directly in the reaction mixture following chloroform extraction orin the reaction vial headspace bysampling with SPME. Separation and identification have been carried out by capillary gas chromatography coupled to electron-ionization mass spectrometry (EI-MS). The results demonstrate that using DMSO aidsGC-MS analysis of spin-trapped free radicals via the formation ofradical-methyl di-adducts that are sufficiently volatile to be sampled both in the headspace or by an extracting solvent without the need for a derivatization step using silylating agents.

• Journal Article Type: Article
• Acceptance Date: Sep 9, 2021
• Online Publication Date: Sep 17, 2021
• Publication Date: Sep 17, 2021
• Deposit Date: Sep 27, 2021
• Publicly Available Date: Oct 1, 2021
• Journal: Free Radical Research
• Print ISSN: 1071-5762
• Electronic ISSN: 1029-2470
• Publisher: Taylor and Francis
• Volume: 55
• Issue: 5
• Pages: 569-578
• DOI: https://doi.org/10.1080/10715762.2021.1980563
• Publisher URL: https://doi.org/10.1080/10715762.2021.1980563
• Related Public URLs: https://www.tandfonline.com/toc/ifra20/current