“…Whilst the analytical value of these approaches has been amply demonstrated relatively less effort has been devoted to exploring, quantitatively, the adsorption characteristics of metals on modified surfaces. Mandler and Downard used some modified electrodes such as crown ether modified glassy carbon electrode [12], mercaptoalkanoic acid on gold electrode [14], cysteamine self assembled monolayer on gold electrode [16], 1,9-nonadithiol on gold electrode [17], enzyme layers on glassy carbon electrodes [18], and alizarin modified on screen printed electrode [19] for the determination of heavy metal ions. In this paper we attempt to determine the adsorption isotherm characteristics of two model toxic metal cations on a glutathione modified carbon surface, and seek to encourage further development in the area such as making sensors for these species but more particularly providing an approach for the intelligent optimization of sensor materials.…”