title: Collision-induced dissociation analysis of negative atmospheric ion adducts in atmospheric pressure corona discharge ionization mass spectrometry.
abstract: Collision-induced dissociation (CID) experiments were performed on atmospheric ion adducts [M + R](-) formed between various types of organic compounds M and atmospheric negative ions R(-) [such as O2(-), HCO3(-), COO(-)(COOH), NO2(-), NO3(-), and NO3(-)(HNO3)] in negative-ion mode atmospheric pressure corona discharge ionization (APCDI) mass spectrometry. All of the [M + R](-) adducts were fragmented to form deprotonated analytes [M - H](-) and/or atmospheric ions R(-), whose intensities in the CID spectra were dependent on the proton affinities of the [M - H](-) and R(-) fragments. Precursor ions [M + R](-) for which R(-) have higher proton affinities than [M - H](-) formed [M - H](-) as the dominant product. Furthermore, the CID of the adducts with HCO3(-) and NO3(-)(HNO3) led to other product ions such as [M + HO](-) and NO3(-), respectively. The fragmentation behavior of [M + R](-) for each R(-) observed was independent of analyte type (e.g., whether the analyte was aliphatic or aromatic, or possessed certain functional groups).
authors.affiliation: Graduate School of Nanobioscience, Yokohama City University, Kanagawa-ku, Yokohama, Kanagawa, 236-0027, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Sekimoto
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Takayama
mesh_terms: D001274:Atmospheric Pressure; D001639:Bicarbonates / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D010100:Oxygen / Q000737:chemistry; D011522:Protons
chemical_list: D001639:Bicarbonates; D007477:Ions; D011522:Protons; D010100:Oxygen