1P-31 PDF
Fundamental Processes of MALDI (I): Laser Fluence Threshold in In-Source Decay
The influence of laser fluence on the generation of matrix and analyte ions has been studied by using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The formation of different ion species such as molecular ion and protonated molecules depends upon the laser fluence. Lower, medium and higher fluences generated matrix ions, analyte ions and in-source decay (ISD) fragment ions, respectively. It was confirmed that MALDI events regarding electron emission, proton transfer and ISD are dependent upon the laser fluences with the thresholds according to ionic species.