Proton conduction in inkjet-printed reflectin films

Biomolecular proton conducting materials have been touted as promising for seamlessly and directly interfacing natural biological systems with traditional artificial electronics. As such, proton conduction has been explored for a variety of protein- and polypeptide-based materials. Within this context, cephalopod structural proteins called reflectins have demonstrated several favorable properties, including outstanding electrical figures of merit as proton conductors and intrinsic biocompatibility with cellular systems. However, the processing of reflectins into films has typically used low-throughput material-intensive strategies and has often required organic solvents. Herein, we report the preparation of devices from active layers fabricated via inkjet printing of reflectin solubilized in water and the systematic evaluation of their electrical performance. Taken together, our findings represent a step forward in the manufacturing and development of unconventional bioelectronic platforms from the reflectin family of proteins.