An Inkjet-Printed Hydrogen Peroxide Sensor on Paper

Abstract

This work presents a fully inkjet-printed electrochemical sensor on paper for non-enzymatic detection of hydrogen peroxide. A simple and low cost hydrogen peroxide (H2O2) sensing is desired in biomedical and environmental analysis. Enzyme-based sensors have widely been used but the possible chemical and thermal deformation of enzymes during the fabrication of the sensors may influence the stability and reliability of the sensors [1]. An alternative to enzymatic sensing could be electrocatalytic detection utilizing the electrocatalytic property of silver (Ag) nanoparticles in reducing H2O2[2]. In this work, we utilize the same principle for a fully printed sensor on paper. An ink solution containing multi-walled carbon nanotubes and silver nanoparticles has been developed before printing the electrode patterns on paper. Using an office inkjet printer and the developed ink, an electrochemical sensor has been designed and printed as shown in Figures 1(a) and 1(b). A total of 50 prints were applied to form the electrodes with high conductivity. A hydrophobic barrier formed by a wax has also been patterned to prevent a sample solution reaching from electrical contacts. The developed sensor was tested with different concentrations of hydrogen peroxide samples. A custom-made potentiostat circuit was used for testing the sensor. Step voltammetry was used by measure the current response after applying -0.3 V to the working electrode. Figure 1(c) shows preliminary results of the sensor response demonstrating that the working electrode current increased with the concentration of H2O2. In summary, a fully inkjet-printed hydrogen peroxide sensor has been demonstrated and its preliminary results have been obtained. The sensor design is currently under optimization to achieve a lower detection limit and high sensitivity.