Chiral resolution of 2-hydroxy-3-methylbutyric acid without derivatization has been studied by capillary electrophoresis using 2-hydroxypropyl-β-cyclodextrin. Chiral resolution of 2-hydroxy-3-methylbutyric acid without derivatization has been studied by capillary electrophoresis using 2-hydroxypropyl-β-cyclodextrin. 2-Hydroxy-3-methylbutyric acid was employed as internal standard for analysis of ethylene glycol (EG) and γ-hydroxybutyrate (GHB) in whole blood.