ENZYME CONVERSION IMMUNOASSAY FOR DETERMINING TOTAL HOMOCYSTEINE IN PLASMA OR SERUM

A rapid and precise immunoassay for quantification of total homocystei ne in blood samples is presented. The method avoids the use of radiois otopes and chromatographic separations and relies on enzymatic convers ion of homocysteine to S-adenosyl-L-homocysteine, followed by quantifi cation of S-adenosyl-L-homocysteine by an enzyme-linked immunoassay in microtiter format. The within-and between-assay imprecision is <6% an d 8%, respectively, and results by the method show good correlation wi th those by HPLC. Including controls and calibrators in duplicates, 82 samples can be analyzed within 2.5 h. The procedure can be fully auto mated.