Abstract
Background
Hyperhomocysteinemia is a risk factor for the cardiovascular diseases that can be usually reversed with vitamin supplements. Quantitative analysis of homocysteine helps to identify patients who might get benefits from the intervention therapy. Recently, as the automated homocysteine assay (ADVIA Centaur, Bayer, USA) by direct chemiluminesence method has been developed, we evaluated the performance of the ADVIA Centaur immunoassay analyzer for homocysteine.
Methods
The total plasma homocysteine concentrations were measured by ADVIA Centaur and by HPLC (HP1100 series with FLD, Hewlett Packard Co., Germany). To test the linearity, a dilution series was prepared. Between-run and total precision of the ADVIA Centaur assay were evaluated with Bio-Rad Homocysteine Controls for 10 days. The correlation was evaluated using 100 plasma samples from patients. NCCLS guidelines (EP5-A, EP6-P, and EP9-T) were followed to evaluate the ADVIA Centaur homocysteine assay.
Results
In the precision study, within-run and total run coefficients of variation (CV) of ADVIA Centaur assay were below 5%. The linearity was maintained well (R2=0.9978). The comparison study indicated a good correlation between the HPLC and ADVIA Centaur assay, and its correlation coefficient (R) was 0.9690.
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