The doubly labeled water (DLW) method of measuring total energy expenditure (TEE) has emerged as a vital tool in obesity research. It has enabled researchers to assess human energy requirements in health and in disease, to study the etiology of obesity, and to validate tools for the assessment of dietary intake. Picarro proposes to develop novel instruments that will measure oxygen and hydrogen isotope ratios in water with high precision by cavity ring down spectroscopy (CRDS). Currently DLW analysis is performed by only 3 or 4 laboratories in the US, and DLW researchers must send their samples to one of these facilities for analysis. As compared with existing mass spectrometry techniques, the proposed instruments will reduce the cost and difficulty of DLW studies, thus enabling many researchers to perform DLW analysis in their own laboratories. They will be able to perform more research, more quickly, conveniently, and at lower cost. In addition, a field-ready instrument not requiring extensive sample preparation would greatly extend the application's reach of energy expenditure methodology. The instrument could also be used by manufacturers of isotopically enriched water for quality control of their product. The doubly labeled water (DLW) method of measuring total energy expenditure (TEE) has emerged as a vital tool in obesity research. The proposed instruments will reduce the time, cost, and difficulty of DLW studies, thus enabling many researchers to perform DLW analysis in their own laboratories. A field-ready instrument not requiring extensive sample preparation would greatly extend the application's reach of energy expenditure methodology. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Small Business Innovation Research Grants (SBIR) - Phase II (R44)
Project #
5R44RR021297-03
Application #
7294889
Study Section
Special Emphasis Panel (ZRG1-BST-D (12))
Program Officer
Friedman, Fred K
Project Start
2005-02-01
Project End
2009-06-30
Budget Start
2007-07-01
Budget End
2009-06-30
Support Year
3
Fiscal Year
2007
Total Cost
$255,058
Indirect Cost
Name
Picarro, Inc.
Department
Type
DUNS #
046635632
City
Sunnyvale
State
CA
Country
United States
Zip Code
94085
Thorsen, Thomas; Shriver, Timothy; Racine, Natalie et al. (2011) Doubly labeled water analysis using cavity ring-down spectroscopy. Rapid Commun Mass Spectrom 25:3-8
Gupta, Priya; Noone, David; Galewsky, Joseph et al. (2009) Demonstration of high-precision continuous measurements of water vapor isotopologues in laboratory and remote field deployments using wavelength-scanned cavity ring-down spectroscopy (WS-CRDS) technology. Rapid Commun Mass Spectrom 23:2534-42