ZnO-carbon nanomaterials-based hybrid platforms for electrochemical sensing of favipiravir as an antiviral medication for COVID-19

Abstract

Favipiravir (FAV) is an antiviral drug that was recently approved for the management of COVID-19 infection. This work aimed to develop a validated sensitive method, using sensor based on porous reduced graphene oxide decorated with zinc oxide nanoparticles (ZnO-prGO) for the determination of FAV in pharmaceutical and biological samples. FE-SEM images showed that prGO nanosheets were decorated by flower-like ZnO nanoparticles with a diameter in the range of 23–63 nm found to be in good agreement with the reported XRD patterns. Electrochemical test showed that the ZnO-prGO modified carbon paste electrode (ZnO-prGO/CPE) had stronger electrochemical activity and higher effective real surface area than that of prGO/CPE and CPE toward FAV oxidation. Interestingly, ZnO-prGO/CPE indicated an excellent electrocatalytic activity for FAV. Under the optimal experimental conditions, a good linear in the concentration range of 0.05–15 μmol L⁻¹ with the low limit of detection (7.32 nmol L⁻¹) and high sensitivity (8.90 μA μmol L⁻¹) was achieved. Furthermore, the proposed sensor was successfully applied to the determination of FAV in tablets, plasma and urine. The unique physical structure of prGO-ZnO, as well as its chemical and electrical properties, make it ideal to use in sensor technologies.