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Human calcium metabolism including bone resorption measured with {sup 41}Ca tracer

Description: Accelerator mass spectrometry is so sensitive to small quantities of {sup 41}Ca that it might be used as a tracer in the study of human calcium kinetics to generate unique kinds of data. In contrast with the use of other Ca isotopic tracers, {sup 41}Ca tracer can be so administered that the tracer movements between the various body pools achieve a quasi steady state. Resorbing bone may thus be directly measured. We have tested such a protocol against a conventional stable isotope experiment with good agreement.
Date: August 1, 1996
Creator: Freeman, S.P.H.T.; King, J.C.; Vieira, N.E.; Woodhouse, L.R. & Yergey, A.L.
Partner: UNT Libraries Government Documents Department

Biological sample preparation and {sup 41}Ca AMS measurement at LLNL

Description: Calcium metabolism in biology may be better understood by the use of {sup 41}Ca labels, although detection by accelerator mass spectrometry (AMS) is required. Methodologies for preparation of urine samples and subsequent AMS measurement were investigated. Novel attempts at preparing CaH{sub 2} were unsuccessful, but CaF{sub 2} of sufficient purity could be produced by precipitation of calcium from urine as oxalate, followed by separation of calcium by cation exchange chromatography and washing the CaF{sub 2} precipitate. The presence of some remaining impurities could be compensated for by selecting the appropriate accelerated ion charge state for AMS. The use of projectile x rays for isobar discrimination was explored as an alternative to the conventional dE/dx device.
Date: October 10, 1994
Creator: Freeman, S. P. H. T.; Southon, J. R.; Bench, G. S.; McAninch, J. E.; Serfass, R. E.; Fang, Y. et al.
Partner: UNT Libraries Government Documents Department