The Influence of the Substrate on Ultraviolet Laser Desorption Mass Spectrometry of Biomolecules

Several investigators have reported that for Laser Desorption Mass Spectrometry (LDMS) with pulsed infrared lasers and foci of about 1 mm the absorption and/or heat conduction properties of the substrate have a strong influence on the spectra obtained [1, 2, 3]. For these types of LDMS, resonant absorption of the laser radiation by the sample has also been shown to effect the types and intensity of desorbed ions [4, 5]. The influence of resonant absorption and of the substrate properties either singly or as combined effects are as yet unknown,or discussed controversially for UV-LDMS [6, 7, 8].