Using HPLC to analyze (S)-oxiracetam and four related substances in the bulk drug of (S)-oxiracetam

Abstract

(S)-oxiracetam is undergoing clinical trials as an active ingredient in the racemic oxiracetam. Here, we report a specific analytical method for analyzing (S)-oxiracetam and four related impurities in the bulk drug of (S)-oxiracetam by using high-performance liquid chromatography (HPLC) system. The chromatographic system included a Capcell pak NH2 analytical column, a mobile phase containing acetonitrile-water (95:5, v/v; pH adjusted to 2.0 with trifluoroacetic acid) at a flow rate of 1.0 mL/min, column temperature at 35 ℃ and the UV detection wavelength is set at 210 nm. This analytical method has shown effective and specific analysis for (S)-oxiracetam and four related substances. Moreover, the molecular weight and chemical structure preliminarily speculated of related substances were characterized by mass spectrometry. The methodology was verified by HPLC and results collected of the method validation included the system suitability, specificity sensitivity, linearity and accuracy, good linear correlation coefficient R2 was more than 0.9991. The analytical method developed and verified in the study, as far as we know, is the most exhaustive HPLC determination report which could be applied for the quality control and stability monitor purposes of the bulk drug of (S)-oxiracetam in the routine pharmaceutical analysis.