Douglas P. Ridge
Metal clusters, proteins and peptides and polymers as studied by mass spectrometry have been the subject of recent work. The capabilities of Fourier transform mass spectrometry (FTMS) to trap and manipulate gas phase ions and to measure masses with great accuracy and precision has made this work possible. The metal clusters vary from metal carbonyl clusters formed in ion molecule reactions to metal sulfide and oxide clusters found in environmental water sources and sampled using laser desorptive ionization (LDI). Electrospray ionization (ESI) provides access to protein and peptide ions and metal sulfide and oxide clusters. Polymers usually provide informative ions on LDI as well. The studies provide information on the structure, energetics and reactivity of the gas phase ions observed using FTMS. The state of the art FTMS instruments used have recently been updated with funds from NSF and the university. Recent developments include obtaining vibrational spectra of unusual gas phase metal carbonyl cluster ions, the verification of the occurrence of metal sulfide clusters of biological and geological importance in Delaware river water, the determination of the primary and secondary structure of gas phase peptide ions, and new methods to determine the molecular weights of polyolefins.