A Validated high Performance Liquid Chromatographic Method for the Quantification of Favipiravir by PDA Detector

Favipiravir is an antiviral agent showing activity for the treatment of various life threatening viruses such as Ebola virus, Lassa virus and also recent virus for COVID-19. It is a pyrazine carboxamide derivative with activity against RNA viruses which targets RNA-dependent RNA polymerase enzymes which are necessary for the transcription and replication of viral genomes. The lack of research work and no compendial methods available for the estimation of this drug influenced the current research investigation to give a simple, sensitive, rapid, precise, accurate and robust isocratic high performance liquid chromatographic and UV Spectroscopic method for the determination and quantification of Favipiravir. The elution was done by using SHIMADZU Prominence-i, LC-2030 C system equipped with Shim-Pack GIST C18 (250X 4.6 mm, 5μm) column with a mobile phase mixture of 10 mM potassium dihydrogen ortho phosphate buffer (pH 4.0) and acetonitrile in the ratio of 90:10 v/v at a flow rate of 1.0 ml/min. The ultraviolet detection was done at the wavelength of 315 nm by maintaining column temperature at 30°. The total run time was 8.0 min. Calibration plot showed best regression over the concentration range of 10-60 μg/ml of Favipiravir standard solutions. The LOD and LOQ was found to be 0.18 μg/ml and 0.53 μg/ml, respectively. The accuracy of the proposed method was determined by performing recovery studies and was found to be between 99.47-100.80%. The repeatability testing for both sample and standard solutions was found as %RSD<2.0% which is within the acceptable limits showing that the method is precise as well. The proposed method was successfully applied for the marketed formulations of Favipiravir tablets. In addition the main features of the proposed method are economic and eco-friendly with less retention time around 4.622 min.