Elsevier

Clinica Chimica Acta

Volume 145, Issue 1, 15 January 1985, Pages 69-76
Clinica Chimica Acta

Valproylcarnitine: a novel drug metabolite identified by fast atom bombardment and thermospray liquid chromatography-mass spectrometry

https://doi.org/10.1016/0009-8981(85)90020-8Get rights and content

Abstract

Urine samples from three children at different stages of chronic valproate therapy were partially purified using a cation exchange column. A signal consistent with either valproylcarnitine or octanoylcamitine was observed in one of these extracts by direct fast atom bombardment-mass spectrometry analysis. These isomeric acylcarnitines were synthesized, separated and characterized by thermospray high performance liquid chromatography-mass spectrometry. This new technique was then employed to positively identify intact valproyl-camitine in the patients' urine samples. The implications of this finding with regard to a mechanism to account for carnitine deficiency in patients receiving valproate are discussed.

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This study was supported in part by a grant from the National Reye's Syndrome Foundation, Bryan, OH; the Reye's Syndrome Research Fund — SFA (Duke University Medical Center) and RR-30 General Clinical Research Centers Program, Division of Research Resources, National Institutes of Health, Bethesda, MD, USA.

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