title: Identification of a radical formed in the reaction mixtures of oxidized phosphatidylcholine with ferrous ions using HPLC-ESR and HPLC-ESR-MS.
abstract: Identification of free radicals was performed for the reaction mixtures of autoxidized 1,2-dilinoleoylphosphatidylcholine (DLPC) with ferrous ions (or DLPC hydroperoxide with ferrous ions) and of DLPC with soybean lipoxygenase using electron spin resonance (ESR), high performance liquid chromatography (HPLC)--ESR and HPLC--ESR-mass spectrometry (MS) combined use of spin trapping technique. ESR measurements of the reaction mixtures showed prominent signals with hyperfine coupling constants (a(N)=1.58 mT and a(H)beta=0.26 mT). Outstanding peaks with almost same retention times (autoxidized DLPC, 36.9 min; DLPC hydroperoxide, 35.0 min; DLPC with soybean lipoxygenase, 37.1 min) were observed on the elution profile of the HPLC--ESR analyses of the reaction mixtures. HPLC--ESR--MS analyses of the reaction mixtures gave two ions at m/z 266 and 179, suggesting that 4-POBN/pentyl radical adduct forms in these reaction mixtures.
authors.affiliation: Department of Pharmacology, Wakayama Medical University, 811-1 Kimiidera, Wakayama, 641-8509, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Kumamoto
authors.forename: Tomihiro
authors.initials: T
authors.lastname: Hirai
authors.forename: Shiroh
authors.initials: S
authors.lastname: Kishioka
authors.forename: Hideo
authors.initials: H
authors.lastname: Iwahashi
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D005296:Ferrous Compounds; D005609:Free Radicals / Q000032:analysis*; D006861:Hydrogen Peroxide; D007477:Ions; D007501:Iron / Q000737:chemistry*; D008084:Lipoxygenase; D013058:Mass Spectrometry; D010713:Phosphatidylcholines / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds; D019097:Spin Trapping
chemical_list: C508476:1,2-dilinolenoylphosphatidylcholine; D005296:Ferrous Compounds; D005609:Free Radicals; D007477:Ions; D010713:Phosphatidylcholines; D000644:Quaternary Ammonium Compounds; C038178:ammonium ferrous sulfate; D006861:Hydrogen Peroxide; D007501:Iron; D008084:Lipoxygenase