Screen-printed textile substrates’ suitability as a platform for electrochemical sensors’ construction
Nuna G. Costa, Cláudia S. Buga, Natália C. Homem, Antonio J. Paleo, Vítor Sencadas, Júlio C. Viana, A. J. Gonzales, Joana C. Antunes, A. M. Rocha
Abstract
• Development of an eco-friendly electrochemical textile-based sensor using recycled polyester and hemp fibers. • Textile-based SPE shows better electrochemical behavior and 1.58% RSD for 20 measurements, outperforming commercial SPEs. • Natural, renewable, cost-effective material, compatible with health applications and easy integration into wearables. • Sustainable materials reduce the environmental impact of discarded SPEs, promoting sustainability in point-of-care devices. • Offers flexibility and comfort for continuous health monitoring while maintaining high electrochemical performance. Electronic sensors are essential in applications like biosensors and fuel cells, providing rapid solutions for substance detection. Integrating electrochemical sensors into textiles offers advantages such as flexibility, comfort, and potential for wearable applications. This study explores the suitability of three textile substrates—100 % polyester knit mesh (S1), 100 % recycled polyester knit mesh (S2), and 50 % recycled polyester/50 % hemp fabric (S3)—for constructing screen-printed electrodes (SPEs). The goal is to develop a textile-based electrochemical sensor with a 3-electrode system (reference, auxiliary, and working electrode) using semi-automated screen printing. The electrochemical performance of two carbon inks, Elantas 9553 and DuPont BQ242, was evaluated to select the best working electrode (WE) ink. DuPont BQ242 was found most suitable for WE production, exhibiting quasi-reversible behavior and temperature stability. The electrochemical behavior of the textile-SPEs printed with DuPont BQ242 revealed that substrate S3 had superior properties, with higher peak currents (peak current ratio of 1.2) and smaller peak potential separation (602 n/V). Carbon Elantas 9553 was more sensitive to temperature changes (1 % variation) than the more stable DuPont BQ242 (0.03 % variation). The stability of the inks on substrates was examined using the 4-point probe method, highlighting excellent electrical stability under UV, high temperatures, cosmetics, and artificial sweat. The final textile-based SPE outperformed commercial SPEs, showing superior redox properties, with a peak potential separation (ΔEp) 56 % smaller and a relative standard deviation (RSD) of 1.58 % over 20 measurements. These textile-based SPEs present a valuable alternative to conventional rigid sensors, which are typically single-use and less durable.