Oxygen isotope ratio measurements on carbon dioxide generated by reaction of microliter quantities of biological fluids with guanidine hydrochloride

Journal Article · Sun Mar 01 04:00:00 EST 1987 · Anal. Chem.; (United States)

DOI:https://doi.org/10.1021/ac00132a002· OSTI ID:6813682

Wong, W W; Lee, L S; Klein, P D

Guanidine hydrochloride was used to convert water in biological fluids to carbon dioxide for oxygen isotope ratio measurements. Five 10-..mu..L aliquots each of five different saliva, urine, plasma, and human milk samples were allowed to react with 100 mg of guanidine hydrochloride at 260/sup 0/C to produce ammonia and carbon dioxide. Ammonia was removed with 100% phosphoric acid and carbon dioxide was cryogenically purified before isotope ratio measurement. At natural abundances, the delta/sup 18/O values of the biological fluids were reproducible to within 0.16% (standard deviation) and accurate to within 0.11 +/- 0.73% (x vector +/- SD) of the H/sub 2/O-CO/sub 2/ equilibration values. At a 250% enrichment level of /sup 18/O, the delta/sup 18/O values of the biological fluids were reproducible to within 0.95% and accurate to -1.27 +/- 2.25%.

• Research Organization: Baylor College of Medicine, Houston, TX
• OSTI ID: 6813682
• Journal Information: Anal. Chem.; (United States), Journal Name: Anal. Chem.; (United States) Vol. 59:5; ISSN ANCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400105* -- Separation Procedures
ABUNDANCE
AMMONIA
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BLOOD
BLOOD PLASMA
BODY FLUIDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBONIC ACID DERIVATIVES
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
DATA
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
FOOD
GUANIDINES
HYDRIDES
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
ISOTOPE RATIO
ISOTOPES
LIGHT NUCLEI
MASS SPECTROSCOPY
MATERIALS
MILK
NATURAL OCCURRENCE
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN 16
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
QUANTITATIVE CHEMICAL ANALYSIS
REMOVAL
SALIVA
SPECTROSCOPY
STABLE ISOTOPES
URINE
WASTES
WATER