Analysis of 25 hydroxyvitamin D^sub 3^ (25OHD^sub 3)^ and 25 hydroxyvitamin D^sub 2^ (25OHD^sub 2^) in human serum using liquid chromatography-tandem mass spectrometry

From: Clinical Chemistry | Date: June 1, 2006| Author: | Copyright information

E-50

H. Chen, L. McCoy, R. L. Schleicher. Centers for Disease Control and Prevention, Atlanta, GA,

A liquid chromalography-tandem mass spectrometry assay was developed for the quantitative analysis of 25OHD^sub 3^ and 25OHD^sub 2^ in human serum. After protein precipitation, analytes were extracted from the matrix using an online solid-phase extraction procedure (Vogeser M. et al. Clin. Chem. 50:8, 2004) involving a Waters Oasis HLB® column in combination with a 10-port high-pressure switching valve. The analytical chromatography was performed using a Supelcosil(TM) LC-18-DB 3µm, 30x3 mm ...

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