title: Photochemically induced transformation of adrenochrome to adrenochrome-melanin.
abstract: The photochemical decomposition of adrenochrome in aqueous and deuterated solutions by visible light was investigated. From the spectroscopic study the disappearance constant k = 4.8 x 10(-5) s-1 as well as quenching constant kq = 2.5 x 10(-1) [s M-1] and isotope effect kD/kH = 2 for singlet oxygen mechanism have been calculated. A possible chemical mechanism for the observed transformation of adrenochrome to the melanin polymer is discussed including the formation of the reactive intermediate species like cytotoxic quinones.
authors.affiliation: Department of Physics, Agricultural University, Poznan, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Polewiski
authors.forename: D
authors.initials: D
authors.lastname: Slawinska
mesh_terms: D000323:Adrenochrome / Q000737:chemistry* / Q000528:radiation effects; D001386:Azides / Q000737:chemistry; D016166:Free Radical Scavengers; D006861:Hydrogen Peroxide / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008027:Light; D008543:Melanins / Q000737:chemistry* / Q000528:radiation effects; D010084:Oxidation-Reduction; D010777:Photochemistry; D019810:Sodium Azide
chemical_list: D001386:Azides; D016166:Free Radical Scavengers; D008543:Melanins; D000323:Adrenochrome; D019810:Sodium Azide; D006861:Hydrogen Peroxide