Method development and validation for the estimation of umifenovir in bulk and tablet formulation by UV-spectrophotometric and RP-HPLC

Umifenovir, an antiviral drug that is used to treat influenza, has recently been used in COVID-19 infection. According to a literature survey, no UV technique for the estimation of umifenovir has yet been established; hence, there is an imperative need for a simple analytical method. Additionally, we developed an alternative, RP-HPLC method for the estimation of umifenovir. UV spectrophotometry was carried out at 223nm absorption maxima using the solvent methanol. A concentration range of 2-12μg/ml was found to obey Beer's Law, with a correlation coefficient (r2) of 0.9995. A C-18 column (250mm 4.6μm, 5μm) was used for chromatographic separation using isocratic mode. The mixture consisted of acetonitrile: 0.1% trimethylamine (pH adjusted to 2.7 by the addition of orthophosphoric acid) 60:40 as the mobile phase with a flow rate of 1.0 ml/min. The temperature was kept at 25°C, and detection at 223nm was performed using a PDA detector. The estimated percentage of the drug was close to 100%, corresponding to the label claim of the tablet made in the laboratory. The results and statistical study demonstrated the utility of the current methods in the routine evaluation of umifenovir bulk and formulation.