In this work, a complete study is carried out for the optimised, direct and catalyst-free growth of vertically-stacked graphene-based structures targeting at improved performance drug monitoring. The nanostructures, ultimately forming a honeycomb network on the substrate, are fabricated by the implementation and comparison of seven combinations of growth conditions on both Si and SiO₂ substrates. Pivotal features characterising the nanostructures i.e. layer thickness, sheet resistance, surface morphology and sensing performance are considered for verifying the quality and properties of the resulted graphene-based electrodes. The graphene-based sensing platform demonstrating optimum structural and electrochemical performance is finally implemented for drug screening showing high efficiency for the detection of a chemotherapeutic compound at low concentrations.