Instrument: Isotope-ratio Mass Spectrometer
The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer).
Samples were analyzed by the isotope-dilution ICP-MS methods described in Lee et al. 2011, which includes pre-concentration on nitrilotriacetate (NTA) resin and analysis on a Micromass IsoProbe MC-ICP-MS