A single use graphite screen-printed electrode (GSPE) was easily modified, to take advantage of the proven affinity of the nontoxic post-transition metal bismuth (Bi), for metal ions to be detected by Square Wave Anodic Stripping Voltammetry (SWASV). A bismuth oxide (Bi2O3) or a chitosan coated (CS@Bi2O3) nanopowder suspension was drop-casted on the graphite working electrode (WE) surface, giving rise to the precursor of a Bi-modified GSPE. After that, an electrochemical reduction was performed to obtain the Bi– or the CS@Bi–GSPE.X-ray photoelectron spectroscopy and micro-X-ray fluorescence investigations were performed on the graphitic structure pre and post modification. The bismuth oxide deposition amount was considered as critical parameter to sensor performance, indicating a minimum and maximum threshold. Under improved measurement conditions, with a 300 s pre-concentration time, the …