J Lab Med Qual Assur.  2012 Dec;34(2):69-76.

Performance Evaluation of Method for Detecting Serum 25-Hydroxyvitamin D2 and 25-Hydroxyvitamin D3 by Using PerkinElmer MSMS Vitamin D Kit

• Kwak HS
• Chung HJ
• Cho DH
• Kim JE
• Ku ES
• Oh HJ
• Park SY

Abstract

BACKGROUND
Determining the concentration profiles of serum 25-hydroxyvitamin D (25OHD) may aid in the clinical diagnosis and treatment of vitamin D deficiency. To date, the standardized liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay has been used for accurate and precise determination of 25-hydroxyvitamin D levels. Here, we evaluated the performance of the recently developed and introduced PerkinElmer Vitamin D kit and compared the measurements obtained by RIA and LC-MS/MS methods.
METHODS
We evaluated the accuracy, precision, linearity, lower limit of quantification (LLOQ), recovery, and carry-over of the MSMS Vitamin D kit. Clinical specimens from 80 patients were used for the comparison between the MSMS Vitamin D kit (PerkinElmer, USA) and the RIA kit (DiaSorin, USA).
RESULTS
The MSMS Vitamin D kit was found to produce intra-assay and inter-assay coefficients of variation (CVs) of less than 6% for precision and showed a bias of less than 5%. The MSMS Vitamin D kit displayed linearity within the range for total vitamin D levels of 4.5-150 ng/mL, and the lower limit of quantification for 25OHD was 0.38 ng/mL. The RIA measurements of 25OHD showed a correlation of y=0.9931x+0.2216 (r2=0.74) with the LC-MS/MS values.
CONCLUSIONS
The LC-MS/MS assay of 25OHD3 and 25OHD2 showed excellent performance when using the MSMS Vitamin D kit and in terms of 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) derivatization. Further, the results obtained were well correlated with those obtained using the RIA method. Thus, assays using the MSMS Vitamin D kit are considered as more standardized, and they enable quicker and more accurate analysis and help reduce inter-laboratory variation than that by other existing methods.

Keyword

25-hyroxyvitamin D; 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD); Tandem mass spectrometry; Radioimmunoassay (RIA)

MeSH Terms

25-Hydroxyvitamin D 2
Bias (Epidemiology)
Calcifediol
Humans
Mass Spectrometry
Tandem Mass Spectrometry
Triazoles
Vitamin D
Vitamin D Deficiency
Vitamins
25-Hydroxyvitamin D 2
Calcifediol
Triazoles
Vitamin D
Vitamins