Simultaneous analysis of homocysteine and methionine in plasma.
The new isocratic cation exchange method separates up to eight different amino thiols. The separated sample components are detected electrochemically using a gold electrode and the integrated pulsed amperometry. The eluent composition is, for example, 0.15 M sodium perchlorate, 0.02 M perchloric acid and 5% acetonitrile. The report describes the optimization of chromatographic parameters such as column diameter and eluent composition. Quantitative performance is discussed for eight different amino thiols using standards. Also presented is a long term quantitative study for homocysteine and methionine in plasma samples. The preparation of plasma samples is simpler than with the previously reported version of the method. Only a reduction step is required, and neither column switching nor derivatization are necessary.
Jandik
P
P
Dionex Corporation, Sunnyvale, CA 94086, USA.
Cheng
J
J
Evrovski
J
J
Avdalovic
N
N
D002411:Cation Exchange Resins; D002852:Chromatography, Ion Exchange / Q000379:methods; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008715:Methionine / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D002411:Cation Exchange Resins; D006710:Homocysteine; D008715:Methionine