ISSN:
0306-042X
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Measurements of protein and amino acid metabolism in man using stable isotopes and selected ion monitoring gas chromatographic/mass spectrometric techniques are limited by the requirement of relatively high levels of labelling for adequate precision ( 〉 0.05 at % excess). We describe here a means of extending the scope of such studies by measurement of lower levels of enrichment achieved in gaseous CO2 derived from whole blood or protein-bound amino acids following the administration of tracer amounts of appropriately labelled substrates. Construction and operation of a novel glass vacuum line required for this work are described in detail and specific applications relevant to clinical investigations are outlined. Measurements of both the total amount of CO2 and its 13C enrichment are performed in an isotope-ratio mass spectrometer which provides acceptable levels of accuracy and reproducibility for both measurements ( ±0.1% and ±0.0001 at% excess respectively).
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bms.1200110706
