Vitamin D deficiency is a common public health problem in our country. It is possible to find data
reaching 90% in studies about determining deficiency prevalence. In recent years, this deficiency has
been attracted the attention of the press and has directed people to a search for blood level monitoring.
For these reasons, there are also serious increases in the number of vitamin D levels analyses in
laboratories. Due to the high measurement costs per patient, it is also one of the most important
laboratory expenses. It is aimed to develop an simple, sensitive and rapid in-house analysis method in
order to reduce laboratory costs and to determine 25(OH)D2 and D3 forms separately.
Material and Methods: Ultimate 3000HPLC-UV (Dionex, Germany) was used in the development of the
method. Architect 25(OH)D kit (Abbott Diagnostic, USA) were used for method comparison study.
Validation studies were performed using CLSI guidelines(EP5-A2,EP6-A,EP9-A2). Accuracy was evaluated
using Certified Reference Material (UME CRM 1308). For chromatographic separation, reverse phase
150mmX4.6mm,(3.0 μm) ODS-1 (Thermo Scientific,USA) analytical column was used.
Results: Within run, between run and between day precisions (%CV) for 18.9ng/mL 25(OH)D3 were
2.6%, 2.7%, 6.3% and for 57.4ng/mL were 1.8%, 1.8% and 4.8% respectively. For 25(OH)D3, the LOD
was 0.7ng/mL and the LOQ was 2.1ng/mL. Correlation between HPLC-UV and Abbott Architect systems
was evaluated by Passing Bablok regression analysis (y=0,89x+1,81).
Conclusion: The compatibility between HPLC-UV and Abbott Architect suggests that both methods can
be preferred. However,each laboratory should decide according to the their conditions in which the
method is selected for the determination of 25(OH)D. Because in such cases where test performances
are very similar. The number of patients, experienced staff presence and cost-determining parameters
will be more prominent in the selection of methods,