Tandem Mass Spectrometry for the Analysis of Plasma/Serum Acylcarnitines for the Diagnosis of Certain Organic Acidurias and Fatty Acid Oxidation Disorders

Methods Mol Biol. 2022:2546:27-34. doi: 10.1007/978-1-0716-2565-1_3.

Abstract

Acylcarnitines are formed in the mitochondria by esterification between carnitine and acyl-CoAs. This occurs enzymatically via carnitine acyltransferases. Specific acylcarnitines accumulate as a result of various organic acidurias and fatty acid oxidation disorders, and, thus, acylcarnitines profiles are used for the diagnosis of these disorders. Acylcarnitines monitoring can also be used for the follow-up of patients with these disorders. Tandem mass spectrometry (MS/MS) is the most commonly used method for the analysis of acylcarnitines. An MS/MS method for the quantification of a number of acylcarnitines is described. The method involves butylation of acylcarnitines using acidified butanol. Butylated acylcarnitines are analyzed using flow injection and precursor ion scan. Multiple-reaction monitoring (MRM) is used for the analysis of low-molecular-weight acylcarnitines.

Keywords: Fatty acid oxidation defects; Inborn error of metabolism; Inherited metabolic disorders; Medium-chain acyl-CoA dehydrogenase deficiency; Organic acidemia; Organic acidurias; Tandem mass spectrometry.

MeSH terms

  • Carnitine / analogs & derivatives
  • Carnitine / analysis
  • Carnitine Acyltransferases
  • Fatty Acids
  • Humans
  • Lipid Metabolism, Inborn Errors*
  • Tandem Mass Spectrometry* / methods

Substances

  • Fatty Acids
  • acylcarnitine
  • Carnitine Acyltransferases
  • Carnitine