Carbon-based Electrochemical Nanosensors for the Determination of PDE5 Enzyme Inhibitors

Sildenafil (SILC), Verdanafil (VRL) and Tadalafil (TAD), which exhibit phosphodiesterase type 5 (PDE5) properties, are active pharmaceutical ingredients that play an important role in the treatment of erectile dysfunction (ED). Traditional analytical methods such as chromatographic and spectrophotometric methods have been widely used for the determination of PDE5 enzyme inhibitors. Nanosensors that will compete with classical analytical methods have been developed for PDE5 enzyme inhibitors using electrochemical methods. The most preferred carbon nanosensors in these studies are; glassy carbon electrode (GCE), screen-printed glassy carbon electrode (SPGCE), graphite paste electrode (GPE), multi-walled carbon nanotube paste electrode (MWCNTPE), boron-doped diamond electrode (BDDE), and pencil graphite electrode (PGE). In addition, new generation carbon-based composite nanosensors have been preferred. In the production of these hybrid sensors, metal or metal oxide nanoparticles, polymers, bioindicators, and carbon materials have been used on the carbon main electrode surface. This review examines the important validation parameters such as sensitivity, selectivity, and detection limits of carbon nanosensors used for PDE5 inhibitors. In addition, the sensitivities between electrochemical methods were compared. The analytical performances of carbon nanosensors were also examined in detail. As a result, the superior performances of carbon nanomaterials developed in the determination of SILC, TAD, and VRL drug active ingredients were definited.