Quantitation of Pregabalin by HPLC-UV Method using Ninhydrin Derivatization: Development and Validation

Introduction: A simple and reliable high performance liquid chromatographic method has been developed for the quantitative determination of pregabalin in bulk and dosage form. Pregabalin, a gamma amino butyric acid analogue, has negligible sensitivity to UV or fluorescence detection. Hence, it has been derivatized by ninhydrin to form a chromophoric complex that could be quantified by UV detection. Materials and Methods: The concentration of ninhydrin was set to 5 mg/ml and a phosphate buffer solution (pH 7.4) was used as a solvent for the reaction. The resultant complex was separated by HPLC and detected by a UV detector at 569nm wavelength. Results: The developed method showed a linear response within 50 to 600 mu g/mL of pregabalin. The method was accurate with mean recovery values within 100 +/- 2%. The repeatability of the method was established by intra-day and inter-day precision study. Finally, a commercial pregabalin capsule was assayed by the developed HPLC method including ninhydrin derivatization. The result of the mean assay was found to be 100.37 +/- 2.94 %. Conclusion: This is the first time we are reporting pregabalin analysis using ninhydrin derivatization for HPLC analysis. Therefore, the developed method can be considered as a significant improvement in pregabalin quantitation and it can be easily applied for routine quality control tests of pregabalin.