Formation of gas phase macromolecular targets by laser desorption from surfaces

To study biomolecular fragmentation induced by low energy ions, electrons, photons and radicals requires the production of a characterised gas phase target. Previous studies have used thermally evaporated DNA or RNA bases however this technique cannot be applied to a wide range of biomolecules because of fragmentation or decomposition. The technique described here involves the use of IR laser desorption for the production of the target in conjunction with time of flight mass spectrometry for analysis of molecular fragmentation. Characterisation of the targets will be carried out by fluorescent dye tagging and laser induced fluorescence imaging of the target spatial density profiles.