title: Evidence for transfer of radicals between oil-in-water emulsion droplets as detected by the probe (E,E)-3,5-bis(4-phenyl-1,3-butadienyl)-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, BODIPY(665/676.).
abstract: (E,E)-3,5-Bis(4-phenyl-1,3-butadienyl)-4,4-difluoro-4-bora-3a,4a-diaza-s-indacene, BODIPY(665/676), is a lipophilic radical-sensitive fluorescent probe that can be used to study radical-driven lipid autoxidation. The sensitivity of BODIPY(665/676) was studied in the presence of radical initiators di-tert-butyl peroxide and 2,2'-azobis(2,4-dimethyl)valeronitrile (AMVN). In both cases the fluorescence of BODIPY(665/676) changed more in saturated medium-chain triglyceride oil than in linseed or sunflower oils, where the high degree of unsaturation is expected to give more pronounced radical-derived lipid oxidation. It was suggested that BODIPY(665/676), as the only available oxidizable substance in the saturated oil, was directly attacked by radicals, resulting in high rates of probe oxidation, while in the unsaturated oils, radicals attacked either unsaturated fatty acids or BODIPY(665/676), resulting in lower rates of probe oxidation. Confocal microscopy studies with BODIPY(665/676) as a radical-sensitive probe combined with oxygen consumption measurements of mixtures of oil-in-water emulsions showed that radicals could be transferred between oil droplets and thereby spread radical-driven oxidation between neighboring droplets.
authors.affiliation: Department of Food Science, University of Copenhagen , Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark.
authors.forename: Piret
authors.initials: P
authors.lastname: Raudsepp
authors.forename: Dagmar A
authors.initials: DA
authors.lastname: Brüggemann
authors.forename: Mogens L
authors.initials: ML
authors.lastname: Andersen
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D015394:Molecular Structure; D009821:Oils / Q000737:chemistry*; D010084:Oxidation-Reduction; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry*
chemical_list: C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; D001896:Boron Compounds; D004655:Emulsions; D005456:Fluorescent Dyes; D005609:Free Radicals; D009821:Oils; D014867:Water
keywords: BODIPY665/676; autoxidation; confocal laser scanning microscopy; emulsion; radicals