Journal of Pharmaceutical Analysis and Drug Research ISSN: 3108-0839 (Online)

Authors: Dr. Pintu B Prajapati, Hitika B. Patel, Dr. Kunjan Bodiwala, Dr. Shailesh Shah

Abstract: Cilnidipine is used for management of hypertension for end-organ protection. A specific, precise, accurate and robust UV-visible spectrophotometric method was developed and validated for stability study of cilnidipine in acidic and alkaline medium.  Forced degradation studies have been carried out in alkaline, acidic and oxidative conditions. The measurement of cilnidipine was carried out at 240 nm. Proposed spectrophotometric method was validated for its accuracy, precision, linearity and range, robustness, specificity as per ICH guideline Q2 (R1). 33 full factorial design was implemented for robustness studies where scanning pitch, scanning speed and wavelength were selected as factors and absorbance was taken as the response for experimental runs suggested by the software. The developed method is linear in the range of 2 to 12 µg/ml with correlation coefficient being 0.9980. The % relative standard deviation for inter and intraday precision were below 2%. Developed method was applied for estimation of Cilnidipine in pharmaceutical dosage form and degradation kinetic study of cilnidipine in acidic and alkaline medium using full factorial design. 32 full factorial design was implemented for determination of relationship between critical variables temperature and strength of acid and alkali with critical quality attributes % degradation, rate constant, half-life. Using response surface mathematical model, % degradation, rate constant and half-life of cilnidipine were predicted at different degradation conditions. The both hydrolytic reactions were found to follow zero order degradation kinetics.

Keywords: stability indicating, cilnidipine, full factorial design, degradation kinetics, UV-Visible spectrophotometry