Additive Manufacturing Sensor for Stress Biomarker Detection

Abstract

This work presents a new additive manufacturing electrochemical device with conductive graphene and polylactic acid (PLA) filament and its application for epinephrine sensing. A three-electrode configuration based on a screen-printed electrode architecture and an easy-to-connect connector was designed. The sensor surface was chemically treated with dimethylformamide (DMF) to remove the insulating thermoplastic and expose the graphene binding groups. The scanning electron microscopy (SEM) results showed that the surface PLA was removed and the graphene nanofibers exposed, which corroborated the X-ray diffraction spectra (XRD). As a proof of concept, the G-PLA electrode was applied for the determination of epinephrine in human blood samples by square wave voltammetry with a linear range from 4.0 to 100 µmol L−1 and a limit of detection of 0.2 µmol L−1. Based on the results obtained and sensor application, 3D-printed G-PLA proved an excellent choice for epinephrine sensing purposes.