These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Determination of serum 25-hydroxy cholecalciferol using high-performance liquid chromatography: a reliable tool for assessment of vitamin D status. Author: Neyestani TR, Gharavi A, Kalayi A. Journal: Int J Vitam Nutr Res; 2007 Sep; 77(5):341-6. PubMed ID: 18453319. Abstract: This study was undertaken to design and set up a rather simple, reliable, and less expensive high-performance liquid chromatography (HPLC)-based method to assay 25(OH)D as a diagnostic tool for vitamin D assessment. Serum proteins were precipitated using ethanol and, after 10 minutes incubation at room temperature, methanol:isopropanol. The extraction was performed using hexane followed by evaporation under nitrogen flow. The sediment was then reconstituted in methanol and passed through a polypropylene filter. To run the chromatographic analysis, 20 microL of the filtrate was injected to the column. Peaks of 25(OH)D2 and 25(OH)D3 were both detected using a UV detector set at 265 nm. With a flow rate of 1.2 mL/minute, peaks of D3 and D2 vitamers were detected around 9.5 and 10.7 minutes, respectively. The intra- and inter-assay variations were 8.1% and 12.6%, respectively, and the recovery percent was found to be 100 +/- 5%. To compare the procedure with conventional methods, 90 serum samples from subjects (48 females and 42 males) aged 40.5 +/- 13.9 yrs, were analyzed for 25(OH)D using HPLC, competitive protein-binding assay (CPBA), and radioimmunoassay (RIA). Generally, CPBA and RIA assays both showed over-estimation of serum 25(OH)D, compared to HPLC. Though all three methods correlated significantly with each other, with the strongest between HPLC and RIA (r = 0.87, p < 0.001), both RIA and CPBA were found unreliable in detection of some deficient samples.[Abstract] [Full Text] [Related] [New Search]