Development of a label-free electrochemical aptasensor based on diazonium electrodeposition: Application to cadmium detection in water

In this study we have developed a new aptasensor for cadmium (Cd2+) detection in water. Gold electrode surface has been chemically modified by electrochemical reduction of diazonium salt (CMA) with carboxylic acid outward from the surface. This was used amino-modified aptamer immobilization through carbodiimide reaction. Chemical modification characterized cyclic voltammetry (CV) and impedance spectroscopy (EIS). latter also Cd2+ detection. The exhibited good linear relationship between logarithm concentration changes range 10?3 to 10?9 M correlation R2 0.9954. A high sensitivity obtained low limit (LOD) 2.75*10?10 M. Moreover, showed selectivity towards when compared other interferences such as Hg2+, Pb2+ Zn2+. presents simple sensitive approach Cd2+detection aqueous solutions application trace spring water samples.