Isotope Ratio Measurements

The Mayo Clinic Metabolomics Core offers stable isotope-labeled tracer methodologies to investigators across various disciplines. Targeted metabolomics with tracers provide greater insights into the dynamics and fluxes of metabolic pathways, and promise robust statistical models for distinguishing sample classes with better classification accuracy.

The core supports the measurement of protein, glucose, and fat metabolism and gastric-emptying studies using a variety of mass spectrometric techniques. We have established methods for measuring the isotopic enrichment of the following analytes:

Amino acids

[ring-13C6] phenylalanine

[d5] phenylalanine

[1-13C,15N] leucine

[ring-13C6] tyrosine

[d4] tyrosine

[13C] ketoisocaproic Acid

[15N] tyrosine

[1-13C] leucine

[15N] Glutamate

[15N] Urea

[15N] Glutamine

[15N] Ornithine

[15N] Aspartate

[15N] Arginine

[15N] Citrulline

[15N] Proline

[15N] Glycine


[6,6-2H2] glucose

[1-13C] glucose

[U-13C] glucose


[U-13C] palmitate

[U-13C] linoleate

[U-13C] linoleoyl carnitine

[13C4] palmitate

[U-13C] oleoyl carnitine

[2H5] glycerol

[2H9] palmitate

[U-13C] palmitoyl carnitine

[U-13C] 16-ceramide

[U-13C] oleate

[13C4] palmitoyl carnitine

[U-13C] 18:1-ceramide

[1-13C] octanoate


[2H4] cortisol

[2H3] cortisol

[2H3] cortisone

[4-13C] cortisol

[2H7] cortisone

Tricarboxylic acids

[13C] Lactate

[13C] Alanine

[13C] Fumarate

[13C] Succinate

[13C] 2-ketoglutarate

[13C] Malate

[13C] Citrate

[13C] Isocitrate

[13C] Glutamine

[13C] Glutamate




National Institutes of Health (NIH) Public Access Policy requires that all publication that results from NIH funding be uploaded to PubMed Central. Review the process for uploading publications.

All users of the core must cite the Mayo Clinic Metabolomics Resource Core grant as a funding source in any resulting publications. Use this language:

This publication was made possible by Mayo Clinic Metabolomics Resource Core through grant number U24DK100469 from the National Institute of Diabetes and Digestive and Kidney Diseases and originates from the National Institutes of Health Director's Common Fund.