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S C March

Publications and source records attributed to S C March.

10 recordsLinked to original sources
PubMed1975

Tritiation of endotoxin.

Tritiated endotoxin was synthesized by three different methods: (1) sodium boro[3H]hydride reduction of native endotoxin; (2) sodium boro[3H]hydride reduction of endotoxin that had been oxidized previously with sodium metaperiodate; and (3) exposure of dry endotoxin to 3H2 gas. Sodium borohydride reduces aldehyde groups and sodium metaperiodate oxidizes vicinal glycol groups to aldehydes. Chromatographic analysis of the three tritiated endotoxins, using agarose, revealed that the biological activity associated with each labeled product appeared at the void volume, and in each case the biological activity coincided with a peak in radioactivity. The labeled product of the first method had a specific radioactivity of 0.18 mCi/g and a biological activity equal to that of native endotoxin. The labeled products of the second and third methods had specific activities of 2.1 mCi/g and 60.0 mCi/g, respectively, while their biological activities were one hundred-fold less than native endotoxin, as determined by the Limulus amebocyte lysate assay. These three labeled endotoxins are potentially ueled endotoxin.

Biological Assay↗
PubMed1971

Ascorbate sulfate: a urinary metabolite of ascorbic acid in man.

Ascorbate-3-sulfate is a significant metabolite of ascorbic acid excreted in human urine. The characteristics of this compound were determined in experiments in which labeling with carbon-14 and tritium was used coupled with cochromatography with synthetic ascorbate-3-sulfate (both labeled and not labeled with sulfur-35) in a variety of solvent and absorbent systems.

Ascorbic Acid↗