DEVELOPMENT AND VALIDATION OF RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF GABAPENTINE AND NORTRYPTALINE

A simple, precise, rapid, specific and accurate stability indicating reverse phase high performance liquid chromatography method was developed for simultaneous estimation of Gabapentin (GPT) and Nortriptyline (NTL) in pharmaceutical tablet dosage form. Chromatographic separation was performed on Agilent C8, (150 X 4.6mm, 5μm) column, with mobile phase comprising of mixture of buffer: (0.1M ammonium acetate) and methanol in the ratio of 70:30v/v, at the flow rate 1.0 ml/min. The detection was carried out at 254 nm. The retention times of GPT and NTL were found to be 2.66 and 3.58 mins respectively with a run time of 6 mins, theoretical levels for GPT and NTL were 8734 and 8648 respectively, with a resolution of 6.56. As per ICH guidelines the method was validated for linearity, accuracy, precision, limit of detection and limit of quantitation, robustness and ruggedness. Linearity of GPT was found in the range of 800-2400 μg/mL and that for CPG was found to be 20-60 μg/mL. The correlation coefficient for GPT and NTL were 0.999 and 1.000 respectively. The LOD values for GPT and NTL were 2.936 and 2.927 μg/mL respectively. The LOQ values for GPT and NTL were and 9.786 and 9.756 μg/mL respectively. This demonstrates that the developed method is simple, precise, rapid, selective, accurate and reproducible for simultaneous estimation of GPT and NTL tablet dosage form.

Keywords: Gabapentin (GPT), Nortriptyline (NTL), RP-HPLC Method Development and Validation