ISSN:
1052-9306
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A direct mass spectrometric measurement method is developed for the determination of 13C enrichment and chemical purity of a labelled compound. The labelled compound is mixed with various amounts of unlabelled analogue to provide a series of mixtures containing different but comparable quantities of labelled and unlabelled species. Intensity ratios of selected isotopically anologous ions from these two species are determined using selected ion monitoring. Equations are established to relate measured intensity ratios to sample mixture weight ratios, chemical purities of the labelled and unlabelled compounds, ion composition and isotopic abundance of the enriched and unenriched carbons, A non-linear regression procedure, based on the measured intensity ratio, the mixture weight ratio and the known chemical purity of the unlabelled compound, is used to resolve the chemical purity and the isotopic abundance yielding results with standard errors of 1.0 and 0.4%, respectively. This procedure is suitable for compounds labelled with more than 60% of an isotope.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bms.1200121103
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