Measurement of 25-hydroxycholecalciferol in plasma
Villalpando-Hernández, S.; Urquieta-Aguila, B.
Archivos de Investigacion Medica 13(1): 11-16
1982
ISSN/ISBN: 0066-6769 PMID: 7065804 Document Number: 190564
The methods for measuring 25-hydroxycholecalciferol (25OHD3) face great problems in solubilizing this hormone for a radioassay system. A tehnique in which ethanol is used to extract the plasma and solubilize 25OHD3 in a radioanalysis system is described. The extraction efficiency was 85 .+-. 1.3%. The sensitivity of the method was 1.36 ng/l, the intra-assay variance 6.2%, and the inter-assay variance 16.5%. The plasma concentrations of a healthy teenage group were 34.8 .+-. 12.7 ng/l, while those found in a group of working women poorly exposed to sunlight (23.6 .+-. 12.2 ng/l) and in a group of hypocalcemic infants (6.6 .+-. 3.3) were significantly smaller. Both sensitivity and precision of the procedure as well as the 25OHD3 plasma concentration, are analogous to those obtained by other methods.