Energy Expenditure

Medical & Clinical

Understanding of the biological processes that control human and animal physiology can be difficult considering the moral implications that are involved in performing such studies. The use of stable isotope analysis provides a non-invasive approach with no adverse reactions which may be observed through using radioisotopes. The use of enriched isotope tracers with artificially high abundances of minor isotopes provides a relatively simple way of probing subtle biological processes.

Breath Analysis

After your subject has ingested an isotopically labelled meal (e.g. 13C-labelled glucose), exhaled CO2 from the patient will show enrichment in 13C levels relative to 12C. The time taken for the 13C isotope to appear in the exhaled breath gives some indication of the metabolic rate of the subject. Up to 220 breath samples can be analysed using our iso FLOW sample handling system for rapid analysis of large numbers of samples.

Body Fluid Analysis

Dosing a subject (human or animal) with doubly labelled water (e.g. water enriched in both deuterium and 18O) allows the total energy expenditure (TEE) of the subject to be determined. High performance deuterium and 18O isotope analysis of up to 180 saliva, blood and urine samples can be performed via headspace equilibration using the iso FLOW sample handling system.

Biochemical Analysis

To understand more about the complex physiological chemical processes that occur within the body, it is necessary to go beyond coarse breath and body fluid analysis. Our gas and liquid chromatography (GC-IRMS and LC-IRMS) systems are able to perform individual compound stable isotope analysis allowing you to find out more about these complex processes.