Determination of isotope ratios in human tissues enriched with zinc stable isotope tracers using inductively coupled plasma-mass spectrometry (ICP-MS).
Enriched fecal and urine samples were prepared using ion-exchange column chromatography for analysis by Inductively Coupled and Fast Atom Bombardment Mass spectrometry (ICP-MS, FAB-MS) to compare precision between methods. Unenriched samples of human milk, feces, and whole blood were prepared similarly to monitor instrumental precision and analytical error. A least squares fit of the ICP-MS results vs the FAB-MS for 70Zn/64Zn gave a slope of 0.98, with a relative standard deviation (RSD) of only 0.7%. The results for 68Zn/64Zn gave a slope of 0.82, with a RSD of 14%. For unenriched tissues, all potential interferences were removed by the preparation procedure with no significant differences between preparation for isotope ratios of 70Zn/64Zn, 68Zn/64Zn, 67Zn/64Zn, and 66Zn/64Zn. Poisson counting statistics are a major contribution to the total analytical error indicating the usefulness of this procedure for enrichment studies.
Friel
J K
JK
Department of Biochemistry, Memorial University of Newfoundland, St. John's, Canada.
Longerich
H P
HP
Jackson
S E
SE
D000818:Animals; D005243:Feces / Q000737:chemistry; D005260:Female; D006197:Hair / Q000737:chemistry; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008892:Milk / Q000737:chemistry; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014018:Tissue Distribution; D015032:Zinc / Q000032:analysis* / Q000097:blood / Q000652:urine; D015033:Zinc Isotopes
D015033:Zinc Isotopes; D015032:Zinc