Fully integrated screen-printed sulfide-selective sensor on a 3D-printed potentiometric microfluidic platform

Abstract

A crucial challenge to address in environmental and biotechnological fields is the development of automated devices for real-time monitoring of chemicals involved. An alternative to conventional manufacturing of flow analysis-based devices is the use of cost-effective printing technologies. Herein, the production of a 3D-printed microfluidic platform with integrated potentiometric detection is described. The device contains completely integrated therein a second kind sulfide-selective electrode (Ag/Ag2S) and a pseudo-reference electrode (Ag/AgCl). This could be accomplished by splitting the 3D printing stage in two and screen printing the electrodes. Then, the electrodes were morphologically characterized while the device was characterized in terms of its analytical response. Furthermore, tap/river/sea-spiked water samples and wastewater from a biotechnological process were measured and compared against a commercial sensor giving no significant differences. Considering all the current challenges in the fabrication of 3D-printed microfluidic platforms with electrochemical detection for environmental and biotechnological screening applications, this appealing approach could constitute a new paradigm in the production of functional monitoring devices.