DERIVATIVE SPECTROPHOTOMETRIC METHODS FOR THE ANALYSIS AND STABILITY STUDIES OF RANOLAZINE IN BULK AND DOSAGE FORMS

Objectives: The present study aimed to develop simple and accurate first and second-order derivative spectrophotometric methods (1D and 2D) for the assay and stability studies of Ranolazine (RAN) in bulk and dosage forms. Methods: The original UV spectrum of RAN solution in methanol was differentiated instrumentally to generate the first and second derivative spectra which were measured at 278 nm and 283 nm, respectively. The developed methods were then validated as per ICH guidelines and applied for the stability studies. Results: Beer’s law was found to be valid over the concentration range 100-600µg/ml with a correlation coefficient (r) not less than 0.999. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 24µg/ ml and 73 µg/ ml, 17.8 µg/ ml and 53.6 µg/ ml, for 1D and 2D respectively. Good results were also obtained from the assay of RAN tablets (98.6 ± 2.3%, n=3). Studying the stability behavior of RAN using the developed methods reflects its instability under alkaline conditions following the first-order kinetics. Conclusion: The statistical validation at a 95% confidence level proves the developed methods’ sensitivity, precision, accuracy and stability-indicating properties.