Angiotensin II-acetylcholine noncovalent complexes analyzed with MALDI-ion mobility-TOF MS.
Matrix-assisted laser desorption ionization-ion mobility-orthogonal time-of-flight mass spectrometry (MALDI-IM oTOF MS) is a new technique that allows laser desorbed ion to be preseparated on the basis of their shape prior to mas analysis. Using this instrument, we tested the postulate that addition of a quaternary ammonium compound such as acetylcholine to the model phosphorylated peptide angio tensin II would enhance its detection by MALDI in two ways. First of all, the acetylcholine-peptide complex could ionize more efficiently than the bare phosphopeptide. Furthermore the ion mobility could separate the complex ion on the basis of its charge/volume from isobaric interferences, which would otherwise limit detection sensitivity.
Woods
Amina S
AS
NIDA IRP, NIH, Baltimore, MD 21224, USA. awoods@intra.nida.nih.gov
Fuhrer
Katrin
K
Gonin
Marc
M
Egan
Tom
T
Ugarov
Michael
M
Gillig
Kent J
KJ
Schultz
J Albert
JA
D000109:Acetylcholine / Q000737:chemistry*; D000804:Angiotensin II / Q000737:chemistry*; D046911:Macromolecular Substances; D010766:Phosphorylation; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013941:Thymine / Q000031:analogs & derivatives* / Q000737:chemistry; D014227:Triazines
D046911:Macromolecular Substances; D014227:Triazines; D000804:Angiotensin II; C005823:2-thio-6-azathymine; D000109:Acetylcholine; D013941:Thymine