Electrochemical detection of glucose in sweat using a paper-based origami biosensor based on PEDOT:PSS/Ti3C2/MWCNT composite

Origami glucose biosensors utilize folding techniques to create compact, cost-effective devices for monitoring glucose levels and offer great potential in healthcare and diagnostics applications. The origami design of the biosensor allows for easy handling and transport, making it ideal for point-of-care testing in resource-limited areas, especially for individuals with diabetes to monitor glucose levels. This study introduced a novel paper-based origami glucose biosensor with graphite pencil electrodes which directly drawn onto the paper surface. A simple method used to draw two circular areas for effective immobilization of the mediator and glucose oxidase enzyme. A novel mediator composed of MWCNT and Ti3C2 dissolved in PEDOT:PSS ink was introduced to the mediator zone to enhance the paper surface's conductivity, thereby boosting the electron transfer rate from the enzyme region to the electrodes. The mediator ink was produced by using a straightforward one-step process, eliminating the necessity for specialized equipment and intricate synthesis techniques. Also, the mediator composite lowered the applied potential for glucose oxidation reaction according to the high surface area, unique electronic properties, and excellent catalytic activity of the composite. The lower potentials for glucose oxidation are required to avoid the electrochemical oxidation of interfering substances, to reach a high accuracy in the detection of the analyte. With a detection limit of 0.007 mM and linear range of 0.01 mM to 0.4 mM, it covers a wide range of glucose concentrations found in sweat.