Mass Spectrometry Core

Director

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About This Core

The mission of this core is to provide scientific expertise and resources for the administration and analysis of stable  isotopes.

The Mass Spectrometry Core is divided into two sections: Energy Expenditure/Body Composition and Metabolism.

Energy Expenditure/Body Composition 
This section focuses on the measurement of energy expenditure using the doubly labeled water technique.  Additionally, measurements of total body water are performed using either deuterium or oxygen 18. With isotope ratio mass spectrometers, we can accurately and precisely measure the amount of heavy isotopes, such as ¹⁸O and deuterium, in relation to the common isotopes, ¹⁶O and ¹H, for the measurement of energy expenditure in studies of obesity. The instruments are also used to measure ¹⁸O and deuterium as measures of total body water and are used for analysis of ¹³C in breath samples as a marker of gastric motility.

Metabolism 
This section focuses on the measurement of stable isotopes that are used to examine lipid, protein and carbohydrate metabolism. This section uses gas chromatograph/mass spectrometers, for measurement of any stable-isotope-labeled (e.g. ²H, ¹⁵N, ¹³C) organic compound. This equipment is used to examine cholesterol, fatty acids, and glycerol metabolism in studies of cardiovascular disease. Glucose, amino acids, and fatty acids are also measured in studies of obesity and diabetes.