title: New chemical evidence for the ability to generate radical molecular ions of polyenes from ESI and HR-MALDI mass spectrometry.
abstract: We report here new chemical evidence for the generation of radical molecular ions of compounds with a conjugated pi-system (polyene) in ESI and HR-MALDI mass spectrometry. The oxidation potential of the neutral polyenes was calculated by cyclic-voltammetry and the results compared with those previously published for other complex conjugated compounds that have also been shown to form M*+ in ESI-MS. This study clearly demonstrates the correlation between the oxidation potential and the formation of the M*+ for the polyenes studied.
authors.affiliation: Universidade de São Paulo, Faculdade de Ciências Farmaceuticas de Ribeirão Preto, Via do Café S/N, CEP 14040-903, Ribeirão Preto-SP, Brazil.
authors.forename: Thais
authors.initials: T
authors.lastname: Guaratini
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Vessecchi
authors.forename: Francisco C
authors.initials: FC
authors.lastname: Lavarda
authors.forename: Patricia M B G
authors.initials: PM
authors.lastname: Maia Campos
authors.forename: Zeki
authors.initials: Z
authors.lastname: Naal
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Gates
authors.forename: Norberto P
authors.initials: NP
authors.lastname: Lopes
mesh_terms: D000818:Animals; D002338:Carotenoids / Q000032:analysis*; D012176:Retinoids / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
chemical_list: D012176:Retinoids; D002338:Carotenoids