Pulsed laser desorption of biological molecules in supersonic beam mass spectrometry with resonant two-photon ionization detection

1987 ◽  
Vol 59 (8) ◽  
pp. 1082-1088 ◽  
Author(s):  
Roger. Tembreull ◽  
David M. Lubman
1988 ◽  
Vol 42 (3) ◽  
pp. 411-417 ◽  
Author(s):  
Liang Li ◽  
David M. Lubman

Resonant two-photon ionization (R2PI) of nonaromatic peptides is studied with the use of CBZ-derivatization as a means of providing an absorbing aromatic center in the near-UV region at 266 nm. The peptides are then vaporized with a pulsed laser-induced desorption method, with subsequent entrainment of the desorbed neutral species into a supersonic expansion. The CBZ-derivatized peptides are then ionized and mass analyzed in a time-of-flight mass spectrometer. The resulting R2PI/MPI-induced fragmentation-ionization patterns generally yield the molecular ion as well as fragments due to specific bond cleavages which are characteristic of the structure of the peptide. Thus, the resulting mass spectra can be used for identification and structural analysis of these small peptides. Most significantly, the laser-induced fragmentation can be used to distinguish between isomeric peptides containing Ile, Leu, or Nle.


1988 ◽  
Vol 42 (3) ◽  
pp. 418-424 ◽  
Author(s):  
Liang Li ◽  
David M. Lubman

Pulsed laser desorption is used as a means of volatilizing nonvolatile and thermally labile molecules for entrainment into a supersonic jet expansion. The jet expansion provides ultracold molecules whose sharp spectral features are probed by resonant two-photon ionization spectroscopy in a time-of-flight mass spectrometer. Such jet-cooled spectra are demonstrated for tyrosine and related structural analogs. Despite the similarity between these tyrosine-based compounds, electronic spectroscopy is shown to be a sensitive probe of small structural changes in these related biological compounds.


Sign in / Sign up

Export Citation Format

Share Document