title: Manganese oxide nanoparticle-assisted laser desorption/ionization mass spectrometry for medical applications.
abstract: We prepared and characterized manganese oxide magnetic nanoparticles (d=5.6 nm) and developed nanoparticle-assited laser desorption/ionization (nano-PALDI) mass spectrometry. The nanoparticles had MnO2and Mn2O3cores conjugated with hydroxyl and amino groups, and showed paramagnetism at room temperature. The nanoparticles worked as an ionization assisting reagent in mass spectroscopy. The mass spectra showed no background in the lowm/z. The nanoparticles could ionize samples of peptide, drug and proteins (approx. 5000 Da) without using matrix, i.e., 2,5-dihydroxybenzoic acid (DHB), 4-hydroxy-α-cinnamic acid (CHCA) and liquid matrix, as conventional ionization assisting reagents. Post source decay spectra by nano-PALDI mass spectrometry will yield information of the chemical structure of analytes.
authors.affiliation: Japan Advanced Institute of Science and Technology, School of Material Science, 1-1 Asahidai, Nomi city, Ishikawa 923-1292, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Taira
authors.affiliation: Japan Advanced Institute of Science and Technology, School of Material Science, 1-1 Asahidai, Nomi city, Ishikawa 923-1292, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kitajima
authors.affiliation: Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan.
authors.forename: Hikaru
authors.initials: H
authors.lastname: Katayanagi
authors.affiliation: Japan Advanced Institute of Science and Technology, School of Material Science, 1-1 Asahidai, Nomi city, Ishikawa 923-1292, Japan.
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Ichiishi
authors.affiliation: Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan; Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ichiyanagi
keywords: ionization; mass spectrometry; metal oxide; transmission electron microscopy