Aiming to improve the performance of paper-based biosensors, some authors have employed additional electrode modification materials, such as conducting polymers and nanoparticles (NPs), aside from the biomolecules and redox mediators. This trend was followed in the construction of a cholesterol biosensor, based on ChOx as a sensing element [35]. The enzyme was applied by drop cast over a layer of graphene, polyvinylpyrrolidone and polyaniline (PANI) nanocomposite, previously electrosprayed onto the screen-printed carbon electrode (SPCE) surface (Figure 2b). This generated a