Does Favipiravir interact with DNA? Design of electrochemical DNA nanobiosensor to investigate the interaction between DNA and Favipiravir used in the treatment of COVID-19

The SARS-CoV-2 (COVID-19) outbreak has presented a global challenge for both rapid diagnostic tests and therapeutic drugs. In this context, the electrochemical DNA-based biosensor was designed for the investigation of DNA and Favipiravir (FAV) which was one of the drugs used in patients infected SARS-CoV-2 during the pandemic interaction by using bare and multi-walled carbon nanotube (MWCNTs) modified disposable pencil graphite electrode (PGE) for the first time. This drug and its derivatives were used extensively during the pandemic period, and the possible effects of Favipiravir on DNA have not yet been investigated in detail with electrochemical (nano) biosensor technologies. In this study, both the standard form of FAV and the tablet form were used and tested with differential pulse voltammetry (DPV) and cyclic voltammetry (CV) to compare their effects on DNA. Besides, scanning electron microscopy (SEM) was used for the characterization of the developed MWCNTs modified electrochemical DNA biosensor. It was observed that FAV interacts with DNA and causes a significant decrease in the guanine oxidation signal at about +1.00 V. The designed MWCNT-based nanobiosensor was able to detect DNA-Favipiravir drug interaction in FAV concentration as low as 0.66 mu g/mL (LOD) with a linear range from 150 to 500 mu g/mL. Rapid analysis due to short interaction time (nearly 32 min) was performed.