Stable Isotope Facility

University of Wyoming

Elemental Analyzer (EA-IRMS)

δ13C and δ15N of Organic and Inorganic Material

Carbon and nitrogen containing compounds occur in both organic (such as plants and animals) and inorganic (such as soils) systems.  δ¹³ and δ¹⁵N ratios of the material can be determined by isotopic analysis of the CO₂ and N2 generated by the combustion of the material. At SIF, the homogenized sample is accurately weighed into a tin capsule and loaded into the autosampler attached to an elemental analyzer.  The EA is coupled to an IRMS through an open split interface.  When a sample is dropped into the EA, the EA automatically processes the sample, combusting the sample to generate product gases that are then separated using the gas chromatograph.  The separated gases (CO₂ and N₂) are then pass through the open split interface to the IRMS for isotopic analysis (EA-IRMS).

Typical sample size:    1-2 mg (plant), 0.5-1 mg (animal), 5-20 mg (soil)