Derivatization of surface-bound peptides for mass spectrometric detection via threshold single photon ionization.
Chemical derivatization of peptides allows efficient F2 laser single photon ionization (SPI) of Fmoc-derivatized peptides covalently bound to surfaces. Laser desorption photoionization mass spectrometry using 337-nm pulses for desorption and 157.6-nm pulses for threshold SPI forms large ions identified as common peptide fragments bound to either Fmoc or the surface linker. Electronic structure calculations indicate the Fmoc label is behaving as an ionization tag for the entire peptide, lowering the ionization potential of the complex below the 7.87-eV photon energy. This method should allow detection of many molecular species covalently or electrostatically bound to surfaces.
Edirisinghe
Praneeth D
PD
Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA.
Lateef
Syed S
SS
Crot
Carrie A
CA
Hanley
Luke
L
Pellin
Michael J
MJ
Calaway
Wallis F
WF
Moore
Jerry F
JF
D013058:Mass Spectrometry / Q000379:methods*; D010455:Peptides / Q000737:chemistry*; D017785:Photons; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D013499:Surface Properties
D010455:Peptides