Flexible Inkjet Printed Gold based Electrochemical Sensor for Aqueous Lead Detection

Abstract

This work presents a novel simple, flexible, cost-effective, sensitive, and disposable inkjet printed (IP) electrochemical sensor on PPG Teslin SP600 substrate for aqueous lead (II) detection. The electrochemical cell contains a gold (Au) working electrode (WE), Au counter electrode (CE), and integrated silver chloride (AgCl) reference electrode (RE). The lateral dimension and area of the fabricated inkjet printed flexible (IPF) electrochemical sensor are 12×8×0.52 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> and 3.41 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> respectively. The reported sensor is initially IP using silver (Ag) nanoparticle conductive ink. The Au WE and CE are obtained with 24K brush Au-plating technology. AgCl formation occurred with dilute sodium hypochlorite (3%) immersion of the sintered Ag RE. The electrochemical sensor is characterized with 3mM of lead (II) contaminated optimized drinking water (0.1 M HCl). The fabricated novel IPF sensor is further utilized for 14.4 µg/L lead (II) contaminated optimized drinking water which is below the United States Environmental Protection Agency approved lead (II) level in the drinking water – 15 µg/L. The fabrication and characteristics/performance of the IPF electrochemical sensor were analyzed using scanning electron micrograph (SEM) images/ energy dispersive X-ray spectroscopy (EDS) and cyclic voltammetry (CV) electrochemical analyses respectively.