title: Characterization of radical adducts formed during photochemical spin trapping in liposomes.
abstract: There exists an urgent need to monitor radical reactions in biological membranes. With the exception of a few studies in model and natural membranes, most biological spin trapping reactions have been confined to homogeneous media. In the present work we have devised a methodology by which spin trapping reactions can be investigated in liposomes composed of a fully-saturated phospholipid, dimyristoylphosphatidylcholine. Using photochemical spin trapping, we have detected and characterized the formation and partitioning of spin adducts in liposomes. Benzophenone (a lipid-soluble photosensitizer) and benzoyl peroxide (a lipid-soluble radical initiator) have been used to generate free radicals from hydrogen donors during photolysis in liposomes. Both water-soluble and lipid-soluble spin traps have been used to trap the radicals.
authors.affiliation: Department of Radiology, Medical College of Wisconsin, Milwaukee 53226.
authors.forename: P G
authors.initials: PG
authors.lastname: Sheng
authors.forename: J
authors.initials: J
authors.lastname: Feix
authors.forename: B
authors.initials: B
authors.lastname: Kalyanaraman
mesh_terms: D001577:Benzophenones; D001585:Benzoyl Peroxide; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D008081:Liposomes / Q000737:chemistry*; D008954:Models, Biological; D010782:Photolysis; D011838:Radiation-Sensitizing Agents
chemical_list: D001577:Benzophenones; D005609:Free Radicals; D008081:Liposomes; D011838:Radiation-Sensitizing Agents; C047723:benzophenone; D004134:Dimyristoylphosphatidylcholine; D001585:Benzoyl Peroxide