A new green-validated and highly sensitive electrochemical method for the determination of molnupiravir (MOV) has been developed using cyclic voltammetry. The proposed analytical platform involves the use of a disposable laboratory-made screen-printed reduced graphene oxide 2.5% modified electrode (rGO-SPCE 2.5%) for the first time to measure MOV with high specificity. The surface morphology of the sensor was investigated by using a scanning electron microscope armed with an energy-dispersive X-ray probe. The fabricated sensor attained improved sensitivity when sodium dodecyl sulfate (SDS) surfactant (3 µM) was added to the supporting electrolyte solution of 0.04 M Britton–Robinson buffer at pH 2. The electrochemical activity of rGO-SPCE was examined in comparison with two different working electrodes in order to demonstrate that it was the most competitive sensor for MOV monitoring. The method was validated using differential pulse voltammetry according to ICH guidelines, resulting in good precision, accuracy, specificity, and robustness over a concentration range of 0.152–18.272 µM, with a detection limit of 0.048 µM. The stability investigation demonstrated that rGO-SPCE 2.5% can provide high-stability behavior towards the analyte throughout a six-week period under refrigeration. The fabricated rGO-SPCE 2.5% was successfully employed for the measurement of MOV in pharmaceutical capsules and human biofluids without the interference of endogenous matrix components as well as the commonly used excipient.

A new green-validated and highly sensitive electrochemical method for the determination of molnupiavir (MOV) has been developed using cyclic voltammetry. The proposed analytical platform involves the use of disposable screen-printed reduced graphene oxide 2.5% electrode (SPrGOE 2.5%) for the first time to measure MOV with high specificity. The surface morphology of the sensor was investigated by using a scanning electron microscope armed with an energy-dispersive X-ray probe. The fabricated sensor attains improved sensitivity when sodium dodecyl sulfate (SDS) surfactant was added to the supporting electrolyte solution. Thus, various factors were investigated in order to select the best supporting electrolyte for voltammetric determination of MOV, and the optimum conditions were achieved by employing 0.04 M Britton-Robinson at pH 2, 10-4 M SDS, and SPrGOE 2.5%. Well-defined MOV oxidation peaks were obtained with no reduction peaks in cyclic voltammetry using diffusion-controlled pathways. The method was validated using differential pulse voltammetry according to ICH guidelines, providing it to be precise, accurate, specific, and robust with linearity over a concentration range of 50-6017 ng/mL. The incorporation of the reduced graphene nanoparticles supported the in situ interaction between electrode surface and MOV, improved the selectivity, and reduced the detection limit to the concentration level of 15.98 ng/mL. The stability investigation demonstrated that SPrGOE 2.5% can provide high-stability behavior throughout a three-month period under refrigeration. The fabricated SPrGOE 2.5% was successfully employed for the measurement of MOV in pharmaceutical capsules and human bio-fluids without the interference of endogenous matrix components as well as the commonly used excipient.