Prussian\nBlue Embedded Carbon Thermoplastic Electrodes\nCrafted by Pre-Modification of 3D Printable Filaments

Chemical modification of the electrode\nsurface plays\na crucial\nrole in electrochemical sensor development. 3D printing has provided\nan efficient and accessible approach to manufacturing electrochemical\nsensors; however, there are limited strategies in how to chemically\nmodify electrode surfaces. Novel filaments that mix conductive materials\nand chemical modifiers have shown promise but often require specialized\nequipment and thus are not widely accessible. Therefore, widely used\napproaches focus on deposition into printed electrodes, but these\nelectrodes lack stability over time. Therefore, a new approach to\nthe generation of chemically modified 3D-printed electrodes is required.\nWe established a strategy for the electrodeposition of Prussian blue\n(PB) onto the surface of a carbon black/polylactic acid (CB/PLA) filament,\nwhich was then used to print an electrode that embedded the PB into\nthe CB/PLA. The PB embedded CB/PLA electrode was more stable and had\na wider linear range than electrodeposited PB film CB/PLA electrodes.\nThis unique approach also provides the ability to make chemically\nmodified electrodes with unique surface geometries, and we were able\nto make a glucose biosensor on a PB embedded square grid surface patterned\nCB/PLA electrode. This electrode could detect glucose consumption\nfrom HepG2 cells. Our approach provides a unique, widely accessible,\nand impactful approach for chemically modifying conductive printable\nfilaments to make chemically modified electrodes, which can be used\nto make a range of diverse electrodes for various applications.