title: Design and development of a fluorescent probe for monitoring hydrogen peroxide using photoinduced electron transfer.
abstract: A novel fluorescent probe, 7-hydroxy-2-oxo-N-(2-(diphenylphosphino)ethyl)-2H-chromene-3-carboxamide (DPPEA-HC) was developed for use in monitoring hydrogen peroxide (H2O2) production. DPPEA-HC, which consists of a diphenylphosphine moiety and a 7-hydroxycoumarin moiety, reacts with H2O2 to form DPPEA-HC oxide, which is analogous to the reaction of triphenylphosphine with hydroperoxides such as H2O2 to form triphenylphosphine oxide. Photoinduced electron transfer (PET) was applied in the design of DPPEA-HC. Since the diphenylphosphine moiety and the 7-hydroxycoumarin moiety would act as the PET donor and the acceptor, respectively, it would be expected that DPPEA-HC would rationally cancel the PET process via the formation of DPPEA-HC oxide, based on the calculated energy levels of the donor and the acceptor moieties using the B3LYP/6-31G*//AM1 method. The fluorescence intensity of DPPEA-HC increased on the addition of a H2O2 solution in 100 mM sodium phosphate buffer (pH7.4), as predicted from the energy level calculation and a good correlation between increase in the fluorescence of DPPEA-HC and the concentration of H2O2 was observed. DPPEA-HC was also fluoresced by H2O2, which was enzymatically produced in xanthine/xanthine oxidase/superoxide dismutase (XA/XOD/SOD) system. The increase in the fluorescence of DPPEA-HC in the presence of H2O2 immediately ceased on the addition of catalase (CAT), which catalyzes the disproportionation of H2O2. In addition, DPPEA-HC was found to have a much higher selectivity for H2O2 and a greater resistance to autoxidation than 2',7'-dichlorodihydrofluoresein (DCFH). Time-resolved fluorescence measurements of DPPEA-HC and DPPEA-HC oxide confirmed that the fluorescence off/on switching mechanism of DPPEA-HC is based on the PET on/off control.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 6-10-1, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Soh
authors.forename: Osamu
authors.initials: O
authors.lastname: Sakawaki
authors.forename: Koji
authors.initials: K
authors.lastname: Makihara
authors.forename: Yuka
authors.initials: Y
authors.lastname: Odo
authors.forename: Tuyoshi
authors.initials: T
authors.lastname: Fukaminato
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kawai
authors.forename: Masahiro
authors.initials: M
authors.lastname: Irie
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Imato
mesh_terms: D001578:Benzopyrans / Q000737:chemistry*; D004579:Electron Transport; D005456:Fluorescent Dyes / Q000737:chemistry*; D006860:Hydrogen Bonding; D006861:Hydrogen Peroxide / Q000032:analysis*; D008958:Models, Molecular
chemical_list: C502477:7-hydroxy-2-oxo-N-(2-(diphenylphosphino)ethyl)-2H-chromene-3-carboxamide; D001578:Benzopyrans; D005456:Fluorescent Dyes; D006861:Hydrogen Peroxide