Enantioseparation of d,l-2-hydroxyglutaric acid by capillary electrophoresis with tandem mass spectrometry-Fast and efficient tool for d- and l-2-hydroxyglutaracidurias diagnosis

- Vancomycin is a suitable chiral selector for separation of d,l-2-hydroxyglutaric acid.
- Complete capillary filling method with vancomycin was employed.
- d,l-2-Hydroxyglutaric acid was enantioseparated without derivatization.
- The method was applied for diagnosis of d-2-hydroxyglutaric aciduria in patient urines.

A novel capillary electrophoresis-tandem mass spectrometry method for the enantioseparation and identification of 2-hydroxyglutaric acid enantiomers without derivatization for clinical purposes was described. Vancomycin chloride was used as an efficient chiral selector for the discrimination of 2-hydroxyglutaric acid enantiomers by capillary electrophoresis employed complete capillary filling method. The obtained resolution was 2.05. Hyphenation of CE with tandem mass spectrometry allows a reliable identification of separated enantiomers as well as their quantification. The method was validated and applied for the separation, identification and determination of 2-hydroxyglutaric enantiomers in urine samples obtained from healthy patients and two urine samples obtained from child patients suffering from high urine excretion of 2-hydroxyglutaric acid. Abnormal excretion of d-hydroxyglutaric acid was found in both child urine samples (104.5 ± 2.1 and 2200.0 ± 12.6 mmol/mol of creatinine, respectively). The limits of detection for d- and l-hydroxyglutaric acid were 31 and 38 nmol/L, respectively.