A new 3D-printing-based approach for mass production of laser-reduced graphene oxide (bio)sensors

Additive manufacturing (AM) is a promising method for rapidly and cost-effectively producing (bio)electroanalytical devices. Its advantages include design flexibility and automation of on-demand platforms. However, challenges remain, especially in developing high-performance, ready-to-use 3D-printed sensing surfaces. Herein, a novel, fully 3D-printed approach is proposed that provides a rapid, flexible, and scalable solution for manufacturing electrochemical devices composed entirely of reduced graphene oxide (rGO). In brief, a graphene printing kit was designed and fabricated using AM. The kit includes the sensor base, the printing spatula, and the printing mask; the latter is designed to print GO-films with the desired geometries. Once printed, the GO-film is converted into conductive rGO tracks via a single CO₂ laser treatment. Eventually, the insulation of the sensing zone was achieved via 3D printing. Laser processing was carefully optimized, and the resulting nanostructured surfaces were carefully characterized morphochemically. The electroanalytical potential was broadly demonstrated with common redox-active probes (methylene blue and catechol) and for the analysis of acetaminophen (ACP) and ascorbic acid (AA), demonstrating the ability to operate across different potential windows. Eventually, ACP and AA were simultaneously determined in antipyretic drugs and dietary supplements, yielding acceptable recoveries (Rec. 89-112%; RSD ≤ 7, n=3), confirming the practical potential of the developed platform. Ongoing studies aim to extend this approach to biosensing systems and to explore alternative substrates to broaden its applications.