Development and Validation of a HILIC–HPLC Method for the Quantitative Determination of Favipiravir in Tablet Formulations

Objective: A validated Hydrophilic Interaction Liquid Chromatography (HILIC) method was developed for the quantitative determination of Favipiravir. Methods: The chromatographic analysis was performed using a high-performance liquid chromatography (HPLC) system comprising a diode array detector, vacuum pump, column thermostat, and autosampler (Agilent 1260, Agilent Technologies, Santa Clara, CA, USA). The analysis was conducted on a ZORBAX RRHD HILIC Plus analytical column (95 Å, 2.1 × 150 mm, 1.8 µm). The mobile phase consisted of acetonitrile and water (80:20, v/v). Chromatographic separation was achieved under isocratic elution at a flow rate of 0.8 mL/min, and Favipiravir was detected at a wavelength of 322 nm. Results: The retention time of Favipiravir was 1.8317 ± 0.002 min, with a limit of detection (LOD) of 0.14 μg/mL and a limit of quantification (LOQ) of 0.47 μg/mL. The regression equation was y = 107.54x + 17.034 with a correlation coefficient (r²) of 0.9997. Conclusion: The proposed method was validated in terms of specificity, linearity, accuracy, precision, LOD, and LOQ, and was successfully applied for the quantitative analysis of Favipiravir in tablet formulations.