Skip to main content
University of Wisconsin–Madison

Mass Spectrometry / Proteomics Facility

Isotope Ratio Lab

The UW-Madison Biotechnology Center is currently open and following the university's COVID-19 Response regarding campus operations.


The Isotope Ratio Mass Spectrometry Laboratory was established as a Core Lab in 2013 when Dr. Schoeller and Tim Shriver, Senior Research Specialist, moved their laboratory from Nutritional Sciences to the Biotechnology Center. The IRMS Core Laboratory specializes in the measurement of natural abundance and low enrichments of the stable isotopes of the light elements of hydrogen, carbon, nitrogen, and oxygen in bulk gases, liquids and solids after their conversion to water, carbon dioxide or nitrogen gas.  The relative abundances of 2H/1H, 13C/12C, 15N/14N, 18O/16O are measured with precisions capable of detecting part-per-million differences in the heavy isotope abundances that are valuable to identify biological origins or trace biological pathways.  The laboratory has particularly strong experience in nutritional applications of stable isotopes including the measurement of energy expenditure by doubly labeled water, energy substrate oxidation using stable isotope labeling, or food webs using unlabeled, natural abundance.


Contact information:
Dale Schoeller        

Tim Shriver, M.S.