This proposal is for acquisition of an automated mass spectrometer system which can carry out nitrogen and carbon isotope analyses with a high throughput (about 100 samples per day) at moderate precision. Both sample preparation and analyses are automated in this system. This instrument will be located in a shared-use facility laboratory (Marine Science Institute Analytical Laboratory) which has a full-time professional supervisor. This laboratory will maintain and operate the instrument on a recharge basis, including operator, at low cost to the research projects. Analyses from this equipment would be available to researchers at other institutions as well as UCSB, as is currently the case with the CHN elemental analyzer in this facility. The ability off this instrument to make large numbers of analyses at low cost opens up the use of stable N and C isotopes for tracer studies in a variety of biological systems where such studies have either not been pursued previously or have been hampered by the high cost of analyses, lack of access to facilities for such analyses, or the need for extensive sample preparation. The initial applications will be to investigate the pathways of nitrogen uptake and utilization in symbionts, and to study N inputs and fluxes in marine and freshwater systems.
