title: Letter: Observation of the 16O/18O exchange during electrospray ionization.
abstract: Isotopic exchange approach coupled to high-resolution mass spectrometry has become the power analytical approach for a wide range of analytical and bioanalyticall applications. Considerable efforts have been dedicated to developing fast exchange techniques directly in the ionization source. But all such methods are limited to the hydrogen/deuterium exchange approaches. In this paper we demonstrate that certain types of oxygen atoms can also be exchanged for (18)O on the time scale of the ionization process. Using HIO(3) and NaIO(4) and by infusing the heavy water H(2)(18)O in the ESI source we have demonstrated that it is possible to obtain a high level of oxygen exchange. It was observed that the rate of this exchange depends to a large extent on the temperature of the desolvating capillary of the mass spectrometer. Several other species, such as peptides, oligonucleotides and low weight organic molecules, were subjected to in-ESI (16)O/(18)O exchange but the exchange was not observed.
authors.affiliation: Skolkovo Institute of Science and Technology Novaya St., 100, Skolkovo 143025 Russian Federation. Institute for Energy Problems of Chemical Physics Russian Academy of Sciences Leninskij pr. 38 k.2, 119334 Moscow, Russia. Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow Region, Russia.. yura542@rambler.ru.
authors.forename: Yury
authors.initials: Y
authors.lastname: Kostyukevich
authors.affiliation: Institute for Energy Problems of Chemical Physics Russian Academy of Sciences Leninskij pr. 38 k.2, 119334 Moscow, Russia. Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow Region, Russia.. konoleha@yandex.ru.
authors.forename: Alexey
authors.initials: A
authors.lastname: Kononikhin
authors.affiliation: Emanuel Institute for Biochemical Physics Russian Academy of Sciences Kosygina st. 4, 119334 Moscow, Russia. Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow Region, Russia.. hexapole@gmail.com.
authors.forename: Igor
authors.initials: I
authors.lastname: Popov
authors.affiliation: Skolkovo Institute of Science and Technology Novaya St., 100, Skolkovo 143025 Russian Federation. Institute for Energy Problems of Chemical Physics Russian Academy of Sciences Leninskij pr. 38 k.2, 119334 Moscow, Russia. Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow Region, Russia.. ennikolaev@rambler.ru.
authors.forename: Eugene
authors.initials: E
authors.lastname: Nikolaev
mesh_terms: D001704:Biopolymers / Q000032:analysis* / Q000737:chemistry; D041961:Deuterium Exchange Measurement / Q000379:methods*; D017666:Deuterium Oxide / Q000737:chemistry*; D010100:Oxygen / Q000032:analysis / Q000737:chemistry*; D010103:Oxygen Isotopes / Q000032:analysis / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D001704:Biopolymers; D010103:Oxygen Isotopes; D017666:Deuterium Oxide; D010100:Oxygen