A.V. Pento, S.M. Nikiforov
Influence of an external electrostatic field on desorption/ionization efficiency in SALDI method was studied. For this aim a linear time of time-of-flight mass-spectrometer with variable acceleration potential was used. Nitrogen laser with wavelength 337 nm, pulse width 5 ns and energy up to 100 uJ per pulse was used for ion desorption. Energy spread of desorbed ions was studied both analyzing mass-spectrometric peak shape and using the retarding potential technique. It was shown that the energy spread is nonthermal and can be up to 1.5 eV and is due a number of desorbed ions. It was found that the presence of external extracting electric field has no affect on SALDI process efficiency.