Enhancement of electron transfer efficiency in biofuel cell anodes using biocompatible redox-active ferritin and enzyme assemblies

Abstract

Ferritin, a naturally occurring iron storage protein, plays a critical role in iron oxidation-reduction processes, making it a focus of recent research to improve the performance of biofuel cell (BFC) electrodes. The highly stable FeIII/FeII redox pairs within the ferritin core allow for reversible electron release/uptake during electrochemical sweeps, making it potentially applicable as a biocompatible redox mediator. In addition, the outermost protein nanoshell provides an effective anchoring site for strong bridging with active components. This dual functionality positions ferritin as a promising candidate for improving electron transfer efficiency in BFCs. In this study, we used a spin coating-assisted layer-by-layer assembly approach to construct and investigate multilayer structures composed of ferritin and glucose oxidase, with a particular focus on the redox properties of ferritin and its role in mediating electron transfer between enzymes and electrodes. Our results show that the strategic integration of ferritin into BFC anodes significantly enhances both current density and operational stability, representing a significant advancement in the development of high performance BFCs. The study provides critical insights into the design of stable and efficient BFCs and/or biosensors, highlighting the potential of ferritin-based assemblies to drive future innovations in bioelectrochemical technologies. These advances have significant implications for a wide range of applications, including medical devices, environmental monitoring, and renewable energy systems. © 2025 The Royal Society of Chemistry.