Objective: To compare the performance of radioimmunoassay (RIA) with high-performance liquid chromatography (HPLC) and electrochemiluminescence (ECLIA) for the quantification of vitamin D (25OHD). Methods: HPLC method for the determination of 25OHD in human biological samples was developed and compared in terms of accuracy and precision with a commercially available RIA assay. Performance of RIA assay with ECLIA technology for 25OHD analysis was further compared. Results: Median 25OHD levels with HPLC vs. RIA were 50.1. nmol/L (IQ = 17.7-199.4. nmol/L) and 51.1. nmol/L (IQ = 12.5-187.2. nmol/L) respectively, whereas median 25OHD concentration with RIA vs. ECLIA was 32.4. nmol/L (9.98-199.7. nmol/L) and 29.9. nmol/L (4.9-214.6. nmol/L), respectively. Comparison data for HPLC vs. RIA showed RIA = -1.13. +. 1.01 (HPLC) (RMSE = 11.2. nmol/L) and for RIA vs. ECLIA revealed, ECLIA = 3.21. +. 0.9 (RIA) (RMSE9.6. nmol/L). Conclusion: Acceptable correlation was observed among HPLC and RIA and also with RIA and ECLIA in quantification of 25OHD.
- High performance liquid chromatography
- Radio immunoassay
- Vitamin D