Mass spectrometry determines the molecular weight of ionized molecules, from small metabolites to large biological compounds like proteins. New refinements to this technique also allow measurement of the three-dimensional structure of the ions using a method called ion mobility spectrometry. We have new instrumentation that combines laser desorption ionization and/or electrospray ionization with ion mobility and time-of-flight mass spectrometry to provide even more thorough measurements of the actual structures of the ions. This instrumentation is being used to monitor metabolite compounds from plant systems of interest in alternate energy production.
A SULI student would primarily perform experiments on a) optimization of ion source geometry and methodology, and b) identification and quantification of actual metabolites in plant samples. Cross sections measured by ion mobility will be compared with those for candidate structures calculated by computer simulations based on an existing program called MobCal. Experience with computers is desired. The SULI student would also collaborate with grad students in experimental measurements using the instrumentation described above. He/she would learn the basics of mass spectrometry, ion mobility, and ion structure simulations.
Program mentor: Sam Houk, Ames Laboratory Associate and Professor, Iowa State University