Author(s)

Rama Joga Venkata Eranki, Gopichand Inti, Venkatasubramanian Jayaraman, Raghuram Pannala, Sudhakar Rao Vidiyala, Jadi Sree Ramulu

Department of Chemistry, Sri Krishnadevaraya University, Anantapur, India.
Quality & Analytical Development Department, InvaGen Pharmaceuticals, Inc., Hauppauge, USA.
Quality & Analytical Development Department, InvaGen Pharmaceuticals, Inc., Hauppauge, USA Department of Chemistry, Sri Krishnadevaraya University, Anantapur, India.
Quality Assurance Department, ScieGen Pharmaceuticals, Inc., Hauppauge, USA.

A stability indicating LC method was developed for the simultaneous determination of Amlodipine and Benazepril capsules in pharmaceutical dosage form. Efficient chromatographic separation was achieved on Symmetry C₁₈ stationary phase with simple combination of amobile phase containing 750 mL of DI Water, 250 mL of Acetonitrile and 2 mL of Octylamine into suitable container with adjusted pH to 2.50 ± 0.05 with the aid of Ortho phosphoric acid delivered in an isocratic mode and quantification was carried out using UV detection at 240 nm at a flow rate of 1.0 mL·min^-1 with an injection volume of 20 μl and ambient column temperature. This method is capable to detect both the drug components of Amlodipine and Benazepril in presence of their degradation products (Amlodipine Imp-A and Benazepril Impurity-C) with a detection level of 0.05%. Amlodipine/Benazepril in their combination drug product were exposed to thermal, photolytic, hydrolytic and oxidative stress conditions, and the samples were analysed. Peak homogeneity data of Amlodipine and Benazeprilis were obtained using PDA detector, in the stressed sample chromatograms, demonstrating the specificity. The method shows excellent linearity over a range of 0.05%-2.0% for Amlodipine, Amlodipine Impurity-A and 0.05%-5.0% for Benazepril and Benazepril Impurity-C. The correlation coefficient for Amlodipine and Benazepril is 1. The relative standard deviation was always less than 2%. The proposed method was found to be suitable and accurate for quantitative determination and the stability study of Amlodipine and Benazepril in pharmaceutical preparations. The developed HPLC method was validated with respect to linearity & range, accuracy, precision and robustness.

Column Liquid Chromatography; Method Validation; Stability Indicating Study Amlodipine and Benazepril

Eranki, R. , Inti, G. , Jayaraman, V. , Pannala, R. , Vidiyala, S. and Ramulu, J. (2013) New Stability Indicating Method for Quantification of Impurities in Amlodipine and Benazepril Capsules by Validated HPLC. American Journal of Analytical Chemistry, 4, 715-724. doi: 10.4236/ajac.2013.412086.