title: Oxidation of ferrocene derivatives in desorption/lonization on porous silicon.
abstract: In matrix-assisted laser desorption/ionization (MALDI), the true molecular structures of some analytes are not represented by the observed ions due to a redox reaction. In earlier reports, electron transfer from analyte to chemical matrix has been proposed for the oxidation of ferrocene derivatives in MALDI. To address such a redox phenomenon in laser desorption/ionization processes, two ferrocene derivatives, FcCH2CH2Fc and FcCH2NMe2 [Fc:(CsHs)Fe(CsH4)], were analyzed by a matrix-free method, desorption/ionization on porous silicon (DIOS). The oxidized species, Fc+CH2NMe2 and FcCH2CH2Fc+, were detected in the DIOS mass spectra. The results suggested that electron transfer from the analytes to the sample target occurs during the ionization process.
authors.affiliation: Japan Science and Technology Agency, Innovation Plaza Osaka, Wada Project Laboratory, 3-1-10 Technostage, Izumi, Osaka 594-1144, Japan.
authors.forename: Shoji
authors.initials: S
authors.lastname: Okuno
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Oka
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Arakawa