Chemometric Approach Based on Factorial and Box-Behnken Designs for Determination of Anti Coronavirus Drug; Favipiravir in Bulk and Spiked Human Plasma by Green HPLC Method

Abstract

The present work describes development of robust, sensitive and green HPLC method with fluorescence detection for determination of favipiravir (FAV). Fractional factorial design was implemented for screening of different factors affecting chromatographic responses. Box-Behnken design was applied to study and optimize the most critical method parameters. The optimum chromatographic conditions obtained involved the use of 0.1% phosphoric acid solution and isopropanol in the ratio 98:2 % v/v as mobile phase at a flow rate of 0.8 mL/min and column oven temperature of 35ºC. Chromatographic analysis was performed on Eclipse plus® C18 (100 mm×4.6mm ×3.5 μm) column with fluorescence detector set at 361 nm and 432 nm for excitation and emission, respectively. A linear response was obtained over the range of 20 - 240 ng/mL with limit of detection of 2.01 ng/mL and quantitation limit of 6.11 ng/mL. The method was successfully implemented for determination of FAV in its pharmaceutical formulation with mean % recovery ± SD of 99.42 ± 0.59. Moreover, the sensitivity of the method allowed determination of FAV in spiked human plasma over a range of 40 – 240 ng/mL. The combined application of green chemistry and quality by design leads to development of robust green method.