Evaluation of Enzymatic Method using an Automated Chemistry Analyzers for Homocysteine Measurement

Abstract

In clinical practice, homocysteine has gained popularity because its elevated values are strongly associated with an increased risk of cardiovascular disease. More recently, a new enzymatic colorimetric assay for homocysteine in biological sample, suitable for automated clinical analyzers, has been proposed. To evaluate one of these enzymatic methods and compare the results obtained with this method with those of an immunoenzymatic method, thirty-two samples were analyzed for total homocysteine by HiSensⓇ homocysteine reagent on the automated chemistry analyzers TBA 200FR and compared to the widely used immunoenzymatic method ADVIA Centaur. In TBA 200FR, the within-run CVs of two control materials were 3.23% and 0.92%, respectively; the between run CVs were 4.58% and 2.55%, respectively. And in ADVIA 1650, the within-run CVs were 6.81% and 0.99%, respectively; the between run CVs were 9.0% and 3.9%, respectively. The recovery for homocysteine was 100% (60.8 μmol/L), 99.1% (48.64 μmol/L), 96.3% (36.48 μmol/L), 96.1% (24.32 μmol/L), and 92.1% (12.16 μmol/L). The regression equation of TBA 200FR vs. ADVIA Centaur was y=0.9095x–2.5086 (r=0.9632). And the regression equation for the ADVIA 1650 chemistry vs. Immulite 2000 was y=0.8418x + 0.3207 (r=0.9625). In conclusion, this enzymatic method using automated chemistry analyzer for homocysteine assay shows acceptable analytical performance. I suggest that this assay will be suitable for routine analysis.