Enantiomeric separation and estimation of stiripentol by liquid chromatography mass spectrometer in human plasma

Abstract The objective of this research was to develop and validate a sensitive, selective chiral method for an anticonvulsant drug, stiripentol, and its enantiomers in human plasma by liquid chromatography–tandem mass spectrometry. Most chiral compounds are separated and analyzed under normal phase chromatography. However, the challenge, for stiripentol enantiomers, was to develop the method under reverse phase chromatography with high sensitivity having lower limit of quantification as low as 10 ng/mL. Both the enantiomers of stiripentol along with their respective stable‐labeled internal standards (stiripentol, D9) were extracted from human plasma by liquid–liquid extraction technique using very low solvent volume. Separation was done in less than 7.0 min on a reverse phase column (Lux Amylose‐2 5µ, 150 × 4.6 mm column), under isocratic elution with a binary mobile phase operation in the ratio of 50:50 v/v (acetonitrile: 5 mM ammonium acetate buffer solution). Mass spectrometer was used as a detector to quantitate the analytes in positive ion mode, using electrospray ionization mode.