A Screen Printed Phenanthroline-Based Flexible Electrochemical Sensor for Selective Detection of Toxic Heavy Metal Ions

A flexible electrochemical sensor was screen printed on polyethylene terephthalate. Carbonand silver-based inks were used for metallization of the working, counter, and reference electrodes. 1,10-phenanthroline and its derivative naphtho[2,3-a]dipyrido[3,2-h:2',3'-f]phenazine-5,18-dione were synthesized as sensitive layers for Hg
²⁺
and Pb
²⁺
, respectively. Cyclic voltammetry response of the sensor resulted in reduction peaks at 0.2 and -0.6 eV for the selective detection of Hg
²⁺
and Pb
²⁺
, respectively. An 87% and 9% change in the average peak currents were observed for the 50-μM concentration of Pb
²⁺
and Hg
²⁺
, respectively, against a reference signal established for deionized water. The response of the electrochemical sensor demonstrated the use of traditional printing processes and synthesized chemicals for the selective detection of heavy metal ions.