G/In2O3 nanocatalyst modified pencil graphite electrode for the electrochemical detection of Favipiravir

Favipiravir (FVP) was one of the promising medications for the treatment of Covid-19 patients. There are limited studies on the electrochemical performance of FVP. Hence it is interesting to study the electrochemical detection of FVP by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. The G/In2O3 nanocatalyst was prepared by precipitation method and applied on the pencil graphite electrode by drop-cast method, the electrode represented here as G/In2O3/MPGE and used as a working electrode for the detection of FVP in a pH 7 Britton Robinson (BR) buffer. The oxidation signal was seen in the region of 1.0 to 1.23 V. The predicted linear range is between 0.7 to 4.9 mu M. The corresponding limit of detection (LOD) and limit of quantification (LOQ) were found for pure drugs at 0.28 mu M and 0.93 mu M, whereas for samples in commercial tablets, it is 0.23 and 0.79 mu M. The same in the presence of urine medium is 0.30 and 106 mu M, respectively. The developed G/In2O3/MPGE offers good detection, selectivity, reasonable stability, and reproducibility to detect FVP in pure drug, tablet form, and in the presence of urine.