Manufactured Flexible Electrodes for Dopamine Detection: Integration of Conducting Polymer in 3D‐Printed Polylactic Acid

Abstract

Flexible electrochemical sensors based on electroactive materials have emerged as powerful analytical tools for biomedical applications requiring bioanalytes detection. Within this context, 3D printing is a remarkable technology for developing electrochemical devices, due to no design constraints, waste minimization, and batch manufacturing with high reproducibility. However, the fabrication of 3D printed electrodes is still limited by the in‐house fabrication of conductive filaments, which requires the mixture of the electroactive material with melted of thermoplastic polymer (e.g., polylactic acid, PLA). Herein, a simple approach is presented for preparing electrochemical dopamine (DA) biosensors. Specifically, the surface of 3D‐printed PLA specimens, which exhibit an elastic modulus and a tensile strength of 3.7 ± 0.3 GPa and 47 ± 1 MPa, respectively, is activated applying a 0.5 m NaOH solution for 30 min and, subsequently, poly(3,4‐ethylenedioxythiophene) is polymerized in situ using aqueous solvent. The detection of DA with the produced sensors has been demonstrated by cyclic voltammetry, differential pulse voltammetry, and chronoamperometry. In summary, the obtained results reflect that low‐cost electrochemical sensors, which are widely used in medicine and biotechnology, can be rapidly fabricated using the proposed approach that, although based on additive manufacturing, does not require the preparation of conductive filaments.