Simultaneous determination of plasma total homocysteine and methionine by liquid chromatography-tandem mass spectrometry.

Abstract

The sulfur-containing amino acid homocysteine is a cardiac risk factor and a biomarker for several inborn errors of metabolism in methionine synthesis. A simple LC-MS/MS method was developed and validated for determination of homocysteine and methionine in human plasma. Rapid separation was achieved using a reverse phase liquid chromatography. Mass spectrometry identification was performed in positive electrospray ionization mode for homocysteine and methionine. Accuracy, precision, linearity, recovery and sample stability were evaluated in the method validation. The test is applied in diagnosis of homocystinuria and monitoring total homocysteine levels. Moreover, simultaneous measurement of methionine helps in the differentiation of homocystinuria and some cobalamin disorders (such as cblC and cblD defects) without additional amino acid testing. Lastly, this assay is sensitive to detect reduced total homocysteine levels that are possibly seen in sulfocysteinuria and molybdenum cofactor deficiencies.

• Authors: Yi Jiang, Brandon Mistretta, Sarah Elsea, Qin Sun
• Journal: Clinica chimica acta; international journal of clinical chemistry (Clin Chim Acta) Vol. 464 Pg. 93-97 (Jan 2017) ISSN: 1873-3492 [Electronic] Netherlands
• PMID: 27845054 (Publication Type: Journal Article)
• Copyright: Copyright © 2016. Published by Elsevier B.V.

Chemical References

• Homocysteine
• Methionine

Topics

• Blood Chemical Analysis (methods)
• Chromatography, Liquid (methods)
• Homocysteine (blood)
• Humans
• Limit of Detection
• Linear Models
• Methionine (blood)
• Reproducibility of Results
• Tandem Mass Spectrometry (methods)
• Time Factors