TITLE:
New Stability Indicating Method for Quantification of Impurities in Amlodipine and Benazepril Capsules by Validated HPLC
AUTHORS:
Rama Joga Venkata Eranki, Gopichand Inti, Venkatasubramanian Jayaraman, Raghuram Pannala, Sudhakar Rao Vidiyala, Jadi Sree Ramulu
KEYWORDS:
Column Liquid Chromatography; Method Validation; Stability Indicating Study Amlodipine and Benazepril
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.4 No.12,
December
3,
2013
ABSTRACT: 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.