Eco-Friendly Approach to Making 3D-Printed Electrochemical Sensors

Carbon poly­(lactic acid) (PLA)-based 3D-printed electrodes have demonstrated their effectiveness across a diverse spectrum of applications. Nonetheless, the issue of the inadequate natural biodegradability of PLA raises significant sustainability concerns, given the predominate single-use nature of 3D-printed electrochemical sensors. Our study is centered on a systematic approach to understand if reducing the amount of carbon black (CB)/PLA used to make the electrodes can have a significant impact on their performance. CB/PLA electrodes were made with varying amounts of material infill and assessed using cyclic voltammetry with different redox probes. Our findings showcased that there is no difference in the anodic current and electron transfer kinetics of CB/PLA electrodes made using infills from 30% to 100%. When comparing the sensing capabilities of 30% and 100% infill electrodes, no differences were observed in the sensitivity and limit of detection for the measurement of dopamine. Using 30% infill to make electrodes reduces CB/PLA usage by 44%. This approach is of significant utility for the development of 3D-printed electrochemical sensors for a broad range of applications spanning sensing and energy storage. Importantly, this manufacturing approach reduces the use of thermoplastics, which can provide considerable benefits to the environment.