Atmospheric pressure photoionization proton transfer for complex organic mixtures investigated by fourier transform ion cyclotron resonance mass spectrometry.
To further clarify the role of dopant solvent in proton transfer in atmospheric pressure photoionization (APPI), we employ ultrahigh-resolution FT-ICR mass analysis to identify M(+*), [M + H](+), [M - H](-), and [M + D](+) species in toluene or perdeuterotoluene for an equimolar mixture of five pyrrolic and pyridinic nitrogen heterocyclic model compounds, as well as for a complex organic mixture (Canadian Athabasca bitumen middle distillate). In the petroleum sample, the protons in the [M + H](+) species originate primarily from other components of the mixture itself, rather than from the toluene dopant. In contrast to electrospray ionization, in which basic (e.g., pyridinic) species protonate to form [M + H](+) positive ions and acidic (e.g., pyrrolic) species deprotonate to form [M - H](-) negative ions, APPI generates ions from both basic and acidic species in a single positive-ion mass spectrum. Ultrahigh-resolution mass analysis (in this work, m/Deltam(50%) = 500,000, in which Deltam(50%) is the mass spectral peak full width at half-maximum peak height) is needed to distinguish various close mass doublets: (13)C versus (12)CH (4.5 mDa), (13)CH versus (12)CD (2.9 mDa), and H(2) versus D (1.5 mDa).
Purcell
Jeremiah M
JM
National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA.
Hendrickson
Christopher L
CL
Rodgers
Ryan P
RP
Marshall
Alan G
AG
Anal Chem. 2000 Aug 1;72(15):3653-9
10952556
J Mass Spectrom. 2003 Oct;38(10):1113-5
14595862
J Am Soc Mass Spectrom. 1994 Jul;5(7):605-13
24221962
Mass Spectrom Rev. 2003 Sep-Oct;22(5):318-31
12949917
Anal Chem. 1984 Dec;56(14 ):2744-8
6524653
Anal Chem. 2004 Nov 15;76(22):6797-801
15538806
Mass Spectrom Rev. 1998 Jan-Feb;17(1):1-35
9768511
Anal Chem. 2006 Aug 15;78(16):5906-12
16906739
J Am Soc Mass Spectrom. 1995 Jan;6(1):52-6
24222060
Anal Chem. 2003 Jul 1;75(13):3256-62
12964777
Anal Chem. 2002 Nov 1;74(21):5470-9
12433075
Rapid Commun Mass Spectrom. 1996;10(14):1824-8
8953784
Anal Chem. 2001 Oct 1;73(19):4676-81
11605846
Anal Chem. 2003 May 1;75(9):2172-6
12720358
J Am Soc Mass Spectrom. 2007 Jul;18(7):1265-73
17482835
Rapid Commun Mass Spectrom. 2003;17(21):2423-9
14587089
Science. 1989 Oct 6;246(4926):64-71
2675315
J Chromatogr A. 2003 Jun 6;1000(1-2):549-65
12877188