Disposable and Sensitive Electrochemical Determination of Molnupiravir at a Pencil Graphite Electrode (PGE) by Differential Pulse Voltammetry (DPV)

This study describes the sensitive voltammetric determination of the COVID-19 drug, molnupiravir, at a pencil graphite electrode (PGE) which is easily available, inexpensive, disposable, and highly electrochemically active. For comparison purposes, cyclic and differential pulse voltammetric responses of molnupiravir were compared at the carbon paste electrode (CPE) and glassy carbon electrode (GCE). The results show that the oxidation potential of molnupiravir shifts to a more negative direction and the peak current of molnupiravir increases significantly with the PGE compared to the CPE and GCE. The PGE demonstrates remarkable electrocatalysis upon the oxidation of molnupiravir. The detection limit and linear range for molnupiravir were determined to be 7.2 nM and 25 to 1000 nM by differential pulse voltammetry. In addition, the selectivity of PGE is high for molnupiravir. The applicability of the sensor was examined by the analysis of pharmaceutical and artificial blood samples. This low-cost and practical sensor was demonstrated to determine molnupiravir with good accuracy and precision.

Automated summary

This study developed a sensitive electrochemical method for the determination of the COVID-19 drug molnupiravir using a pencil graphite electrode (PGE). The PGE showed more significant oxidation potential shift and peak current increase compared to the carbon paste electrode (CPE) and glassy carbon electrode (GCE). The sensor demonstrated good accuracy and precision in determining molnupiravir.