High performance liquid chromatography with fluorimetric detection for thedetermination of total homocysteine in human plasma: method and clinical applications

Homocysteine (Hcy), an amino acid derived from methionine is an independent risk factor for coronary artery disease. We have developed a convenient hi gh performance liquid chromatography assay with fluorimetric detection for the accurate determination of Hey in human plasma. This assay involves dire ct addition of human plasma to methanolic monobromobimane for simultaneous protein precipitation and thiol derivatization. The assay was validated by adding authentic homocysteine and homocystine to plasma samples with recove ry rates between 95.5 and 102.4%. The relative standard deviations for intr aday (n = 7) and interday (n = 6, 10 consecutive days) analysis were 0.7-3. 9 and 0.7-4.0%, respectively. Reference values of plasma total homocysteine (tHcy) have been determined for men and women, showing a significant diffe rence (P < 0.05) between genders. Preliminary results for occluded coronary artery disease and for maintenance hemodialysis are presented. (C) 2001 El sevier Science B.V. All rights reserved.