| Laser desorption ionization/Fourier transform mass spectrometry is demonstrated to be a versatile method of analyzing a variety of species including biomolecules, large organic species, nonvolatile molecules, alkali metal salts, organic polymers, and synthetic porphyrins. The design, characterization, and application of an alternate method of interfacing laser desorption ionization with FTMS is also described in this work.; A novel, probe mounted fiber optic interface for pulsed high power laser desorption ionization adds an additional degree of freedom to the LDI/FTMS experiment such that the distance between the desorption site and the FTMS trapped ion cell can be varied up to 40 cm in order to optimize the trapping of analyte ions for subsequent detection. The fiber optic, its interfacing with the laser source, and characterization of the power and wavelength capabilities of the interface are described in detail.; Systematic variation of a wide variety of parameters, and assessment of their effects on the quality and content of resulting spectra has produced a greater understanding of the processes involved in trapping ions in the FTMS experiment. Variations in desorption/ionization displacement from the trapped ion cell, trapping potential, laser power, and ejection of unwanted ions in the trapped ion cell demonstrate distinct effects on the spectra of different types of analyte species.; Evaluations of the formation and reactions of the variety of ions produced from alkali metal salts using pulsed, high power infrared laser desorption are discussed, with emphasis on cation attachment reactions as they occur with organic molecules and biomolecules.; Investigations into the spatial and temporal evolution of desorbed/ionized species is undertaken by exploiting the broad distribution of mass spectral peaks produced with polyethylene glycol polymer samples. It is from these experiments that an increased understanding of the relative energies and velocities of analyte molecules and ions, and their propagation through the FTMS spectrometer is inferred.; An examination of the ionization processes of synthetic porphyrins in LDI/FTMS is conducted to determine the method of generation of charged species in mass spectral analysis of these species. |
