title: Superoxidation of retinoic acid.
abstract: Atmospheric pressure chemical ionization mass spectroscopy (APCI-MS) was used to examine the light-induced oxidation products of retinoic acid under conditions that favor and preclude its aggregation. We observed that in conditions that favor aggregation, i.e. in aqueous solutions, retinoic acid undergoes superoxidation to yield highly oxidized species. Oxidation is limited, however, in the absence of such communication, i.e. when the polyene is fully solvated. From a comparison of the measured MS with that obtained from chemical oxidation of retinoic acid under conditions that promote radical oxidation and singlet oxygen-mediated oxidation, we conclude that superoxidation is mediated by reactive oxygen species other than singlet oxygen.
authors.affiliation: Department of Chemistry, Columbia University, New York, NY, USA. iw2101@columbia.edu
authors.forename: Ilyas
authors.initials: I
authors.lastname: Washington
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Turro
authors.forename: Koji
authors.initials: K
authors.lastname: Nakanishi
mesh_terms: D013058:Mass Spectrometry; D008958:Models, Molecular; D008968:Molecular Conformation; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet; D014212:Tretinoin / Q000737:chemistry*
chemical_list: D014212:Tretinoin