“…In order to increase the sensitivity and selectivity towards certain analytes, various carbon-based electrode materials were used by modifying their surfaces with substances that have a selective affinity towards the metal ions of interest [ 17 , 18 ]. Several types of carbon materials, including glassy carbon, graphene, carbon nanotubes, carbon paste, carbon fibers, and SPEs, have been reported as substrate materials for the detection of metal ions [ 19 , 20 , 21 ]. In recent years, screen-printing has been the most used in electroanalysis for the manufacture of sensors and biosensors [ 22 , 23 , 24 ].…”