Fluorimetric Determination of Antiviral (COVID-19) Drug Favipiravir in Bulk and Pharmaceutical Dosage Forms

Abstract

Favipiravir is a synthetic prodrug, which was first discovered while assessing the antiviral activity of chemical agents active against the influenza virus in the chemical library of Toyoma chemicals. It works by inhibiting RNA dependant RNA polymerase (RdRP), an enzyme required for RNA viral replication inside human cells. A simple, rapid, and economic method was developed for the quantitative determination of Favipiravirusing spectrofluorometer. The Favipiravir standard drug solution and sample tablet solution was prepared using double distilled water as a diluent. The different concentrations ofpure drugin the range 2-10 μg/ml and one sample solution were measured for the intensity at 432nm in the spectrofluorometer. The calibration curve was plotted and the sample’s unknown concentration was calculated from the plot. The calibration curve was found to be linear with r2 value obtained as 0.99.There are various other methods available for the quantification of Favipiravir which include RP-HPLC, UV-spectroscopic methods, FTIR, LC-MS with different extraction methods spiked in human plasma but not by using spectrofluorometer. Favipiravir shows fluorescence when dissolved in appropriate solvent hencethis method was developed to quantify Favipiravir which is a simple and efficient method. This method developed is easy and can be used for routine quality control test for Favipiravir pharmaceutical formulations.
 Keywords: Favipiravir, spectrofluorometer, Calibration curve.