Sequential-saturation-type assay for serum 25-hydroxyvitamin D.

G Ellis; K Dixon

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PubMed · 852108

Sequential-saturation-type assay for serum 25-hydroxyvitamin D.

G Ellis·K Dixon

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Abstract

We describe a method for measuring 25-hydroxyvitamin D in serum. The serum is denatured with ethanol, and the extract purified by chromatography on silicic acid to prevent potential interference from vitamin D and by other substances. 25-Hydoxyvitamin D is assayed by sequential saturation analysis in Tris-HCI buffer, pH 8.6, containing the surfactant Triton X-405 (2 ml/liter) to solubilize the steroid. Diluter, unpurifed normal human serum is used as the binder. The method is sensitive and precise. The dose-response curve is linear. The assay normally gives high count rates (12 000 to 20 000 cpm for the zero standard) and consequently 25-hydroxyvitamin D of low specific activity can be used if necessary. Serum 25-hydroxyvitamin D was determined in normal and osteomalacic subjects.

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Blood Proteins Buffers Chromatography, Gel Dihydroxycholecalciferols Female Humans Hydroxycholecalciferols In Vitro Techniques Male Methods Protein Binding Reference Values Time Factors Tritium Journal Article

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G Ellis, K Dixon. 1977. Sequential-saturation-type assay for serum 25-hydroxyvitamin D.. https://pubmed.ncbi.nlm.nih.gov/852108/

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