AFJPS African Journal of Pharmaceutical Sciences 2789-5092 SvedbergOpen afjps-1-1-004 10.51483/AFJPS.1.1.2021.40-46 Research Paper Design and Validation of UV Spectrophotometric Method for Estimation and the Routine Quality Control Analysis of Sildenafil Citrate in Bulk and in Tablet Formulations IbrahimMahmoud A. 1 MagboolFatehalrahman F 2 * GamilAbdrhman Mahmoud 3 AdamMohamd E. 4 1College of Pharmacy, Department of Pharmaceutical Analysis, Ribat National University, Sudan. E-mail: mahmoudbutre@gmail.com 2Department of Pharmaceutics, Faculty of Pharmacy, Al-Neelain University, Sudan. E-mail: fmagbool@yahoo.com 3Department of Pharmaceutics, Faculty of Pharmacy, Al-Neelain University, Sudan. E-mail: Abdrahmangamil@gmail.com 4Department of Chemistry, Faculty of Pharmacy, University of Khartoum, P.O. Box 1998, Khartoum, Sudan. E-mail: dackouk2015@gmail.com *Corresponding author: Fatehalrahman F. Magbool, Department of Pharmaceutics, Faculty of Pharmacy, Al-Neelain University, Sudan. E-mail: fmagbool@yahoo.com 09 2021 1 1 40 46 Abstract

A Simple, sensitive, specific, UV Spectrophotometric method has been designed and developed for the determination of sildenafil citrate in bulk power and in pharmaceutical dosage form as well as its application for the routine quality control analysis of Sildenafil in bulk as well as in tablet formulations. The optimum condition for the analysis of the drug was established. Sildenafil citrate exhibiting absorption at 295 nm. The proposed method exhibited good levels of detection and quantitation. The specificity of the method was determined by checking the interference of placebo with analyte. There was no interference is observed. The regression equation for the Beer-Lambert’s plot of pure Sildenafil citrate was found to be; Y = 0.190 x and the correlation coefficient (R2) of 0.9990. The Beer’s plot was obeyed in concentration range between 0.001-0.005 mg/mL. There is good correlation between absorbance and concentration. Which is the basis of this method of analysis. The repeatability and intermediate precision were also assessed. The developed method was found to be precise as the % RSD values. The application of the validated method to the three brands showed that all brands had values within the range specified in the IP (90110%). The results and the statistical parameters demonstrate that the proposed UV spectrophotometric method is simple, rapid, specific, accurate and precise. Since the method can be used for estimation and routine quality control of Sildenafil in bulk as well as in tablet formulations.

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