Infrared Laser Desorption/Vacuum Ultraviolet Photoionization Mass Spectrometry Technique and Its Preliminary Applications

We introduce a method combining IR laser desorption with tunable synchrotron vacuum ultraviolet photoionization mass spectrometry. The method needs no matrix and sample preparation. Fragment-free mass spectrometric analysis can be accomplished by near-threshold photoionization, while fragments can be formed by increasing photon energy. Mixtures (even isomers) can be distinguished by measurements of photoionization efficiency spectra.