Electrochemical Metallization Process on Screen-Printed Electrode for Creatinine Monitoring Application

Abstract

The formation and dissolution of the conductive paths in an electrochemical metallization (ECM) system is greatly influenced by the mobility of metal ions in the electrolyte, which can be utilized for the sensor application. Here, we report a demonstration of the ECM on the commercially available screen-printed electrode (SPE) strip, which is then utilized for monitoring the concentration of creatinine in an aqueous mixture. Prior to that, the working electrode was modified by drop casting an organic pentamer, 1,4-bis[2-(5-thiophene-2-yl)-1-benzothiopene]-2,5-dioctyloxybenzene (BOBzBT <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ). The electrostatic interaction between the BOBzBT <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> radical cations and the creatinine molecules causes the resistance change in the electrochemical cell, influencing the variation of the ECM-induced pinched hysteresis loop. Consequently, the changes were recorded and the calibration curve was obtained. Compared to the unmodified SPE, the BOBzBT <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -modified SPE demonstrated good performance in monitoring the concentration of creatinine. The sensor demonstrated 60 s response time with a sensitivity of 8.18 A dL g <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> for a linear detection range of 0.7–1.1 mg/dL. The selectivity and reproducibility of the modified sensor was also demonstrated. The setup’s simple fabrication procedures could open the way for the development of an ECM-based SPE sensor for creatinine monitoring.