Portable and On-Demand Yeast Cells-Based Electrochemical Biosensors Enabled by Polydopamine

The electrical wiring of biological organisms with electrodes enables the development of sustainable, low cost, and potentially self-sustained electrochemical biosensors.(1) However, achieving such electrical communication is challenging, particularly when intact biological organisms are employed.<br/>Yeast cells have the advantages of high stability and robustness, self-regeneration capability, and unique eukaryotic receptors. Herein, we developed a bioinspired approach for the rapid entrapment and immobilization of metabolically active yeast cells in a biocompatible polydopamine layer, which does not require a separate and time-consuming synthesis. The obtained biohybrid system allows current generation from glucose oxidation, with electrochemical performance influenced by the presence of CuSO₄, a widely used pesticide, in the environmentally relevant concentration range of 20 - 100 μM.(2) The effect of different substrates on current generation and biosensor sensitivity is discussed, and the enthralling possibility to utilized mutant strains with altered respiratory metabolism for biosensors with enhanced performance is presented.<br/><br/>1. M. Grattieri and S. D. Minteer, <i>ACS Sens.</i>, <b>3</b>, 44 (2018).<br/>2. O. Benjamin Ocheja, E. Wahid, J. Honorio Franco, M. Trotta, C. Guaragnella, E. Marsili, N. Guaragnella and M. Grattieri, <i>Bioelectrochemistry</i>, <b>157</b>, 108658 (2024).<br/><br/><b>Acknowledgments</b><br/>Matteo Grattieri would like to acknowledge the funding from Fondazione CON IL SUD, Grant “Brains to South 2018”, Project No. 2018-PDR-00914.