METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF LEVOSULPIRIDE AND RABEPRAZOLE SODIUM: A NEW ANALYTICAL Q-ABSORBANCE RATIO APPROACH

Objective: The aim of the study was to develop a precise, accurate, and rapid ultraviolet spectrophotometric method for simultaneous estimation of levosulpiride (LEVO) and rabeprazole sodium (RBS) in the binary mixture and to validate the method as per ICH guidelines.Method: Estimation of LEVO and RBS was performed by Q-absorbance method. Analysis was performed using the ratio of absorbance at two selected wavelengths, one at iso-absorptive point and other is the absorbance maxima of any one of the components. Single scan spectrum and the overlain spectrum conclude that absorbance maxima of LEVO and RBS are 228 and 291.8 nm, respectively, with a coinciding iso-absorptive point at 255 nm. Method uses a ratio of absorbance for assay at 255 and the second wavelength is 291.8 nm, λmax for RBS. It is also applicable at 228 nm, as the second wavelength.Results: Linearity of LEVO and RBS was found to be 25-125 and 4-36 μg/ml, respectively. The accuracy of the LEVO and RBS was found 99.26% and 99.51%, respectively and Sandell’s sensitivity ranged between 0.0238 and 0.594 μg/cm2. Assay of LEVO (75 mg) and RBS (20 mg) in capsule dosage form was found 99.5% and 98.69% w/w, respectively.Conclusions: The developed method for the estimation of LEVO and RBS in binary mixture were found to be simple, accurate, robust, and reproducible. No interference of excipients and the degraded product was found during the estimation. Therefore, the method can be successfully applied for routine quality control analysis.RBS) in the binary mixture and to validate the method as per ICH guidelines.Method: Estimation of LEVO and RBS was performed by Q-absorbance method. Analysis was performed using the ratio of absorbance at two selected wavelengths, one at iso-absorptive point and other is the absorbance maxima of any one of the components. Single scan spectrum and the overlain spectrum conclude that absorbance maxima of LEVO and RBS are 228 and 291.8 nm respectively with a coinciding iso-absorptive point at 255 nm. Method uses ratio of absorbance for assay at 255 and the second wavelength is 291.8 nm, λmax for RBS. It is also applicable at 228 nm, as the second wavelength.Results: Linearity of LEVO and RBS were found to be 25-125and 4-36 μg/ml respectively. Accuracy of the LEVO and RBS was found 99.26 and 99.51% respectively and Sandell’s sensitivity ranged between 0.0238 and 0.594 𝜇g/cm2. Assay of LEVO (75 mg) and RBS (20 mg) in capsule dosage form was found 99.5 and 98.69% w/w respectively.Conclusions: The developed method for the estimation of LEVO and RBS in binary mixture were found to be simple, accurate, robust and reproducible. No interference of excipients and the degraded product were found during the estimation. Therefore the method can be successfully applied for routine quality control analysis.