Stability Indicating Analytical Method Development and Validation for Simultaneous Estimation of Pregabalin, Mecobalamin and Alpha Lipoic Acid in Bulk as well as in Pharmaceutical Dosage Form by using RP-HPLC

The present work was undertaken with the aim to develop and validate a rapid and consistent RP-HPLC method in which the peaks will be appear with short period of time as per ICH Guidelines. The proposed method was simple, fast, accurate and precise method for the Quantification of drug in the dosage form, bulk drug as well as for routine analysis in Quality control. RP-HPLC method was developed and validated for simultaneous estimation of Alpha Lipoic Acid, Mecobalamin and Pregabalin in bulk drug and in combined dosage forms.

The HPLC separation was achieved on a Symmetry C₁₈ (4.6 x 100mm, 5.0μm, Make: Thermosil) or equivalent in an Isocratic Mode. The mobile phase was composed of Buffer (60%) whose pH was adjusted to 6.0 by using Ortho Phosphoric Acid, Acetonitrile (20%) [HPLC Grade] and Methanol (20%) [HPLC Grade] The flow rate was monitored at 0.8 ml per min. The wavelength was selected for the detection was 210 nm. The run time was 10min.

The retention time found for the drugs Alpha Lipoic Acid, Mecobalamin and Pregabalin were 1.803 min., 2.506 min. and 6.459 min. respectively. The % recovery was found to be 99.8%-99.8% for the drug Alpha Lipoic Acid. The % recovery was found to be 99.8% -101.3% for the drug Mecobalamin. The % recovery was found to be 99.8% -100.87% for the drug Pregabalin. The linearity was established in the range of 50 to 90ppm for the drug Alpha Lipoic Acid and 0.37 to 0.67ppm for the drug Mecobalamin and 37.5 to 67.5 ppm for the drug Pregabalin. The LOD for the drugs Alpha Lipoic Acid, Mecobalamin and Pregabalin were found to be 0.504μg/ml, 0.0005μg/ml, and 0.35μg/ml respectively. The LOQ for the drugs Alpha Lipoic Acid, Mecobalamin and Pregabalin were found to be 1.3μg/ml, 0.0052μg/ml and 0.866μg/ml respectively. The drug was exposed to Thermal, Hydrolytic and Oxidative stress conditions and the stressed samples were analyzed by the proposed method. The peak homogeneity data for the drugs Alpha Lipoic Acid, Mecobalamin and Pregabalin were obtained by using Photodiode Array Detector in the stressed sample chromatograms which demonstrated the specificity of the method for the estimation in the presence of degradants.

Overall the proposed method was found to be suitable and Accurate for the Quantitative determination and stability study of the drug in Pharmaceutical dosage form. The method was effectively separated the drug from its degradation product and it was employed as a stability-indicating one. The method was simple, precise, accurate and sensitive and applicable for the simultaneous determination of Alpha Lipoic Acid, Mecobalamin and Pregabalin in bulk drug and in combined dosage forms.