Electrically Contacted Bienzyme-Functionalized Mesoporous Carbon Nanoparticle Electrodes: Applications for the Development of Dual Amperometric Biosensors and Multifuel-Driven Biofuel Cells

The capping of electron relay units in mesoporous carbon nanoparticles (MPC NPs) by crosslinking of different enzymes on MPC NPs matrices leads to integrated electrically contacted bienzyme electrodes acting as dual biosensors or as functional bienzyme anodes and cathodes for biofuel cells. The capping of ferrocene methanol and methylene blue in MPC NPs by the crosslinking of glucose oxidase (GOx) and horseradish peroxidase (HRP) yields a functional sensing electrode for both glucose and H₂O₂, which also acts as a bienzyme cascaded system for the indirect detection of glucose. A MPC NP matrix, loaded with ferrocene methanol and capped by GOx/lactate oxidase (LOx), is implemented for the oxidation and detection of both glucose and lactate. Similarly, MPC NPs, loaded with 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), are capped with bilirubin oxidase (BOD) and catalase (Cat), to yield a bienzyme O₂ reduction cathode. A biofuel cell that uses the bienzyme GOx/LOx anode and the BOD/Cat cathode, glucose and/or lactate as fuels, and O₂ and/or H₂O₂ as oxidizers is assembled, revealing a power efficiency of ≈90 μW cm^-2 in the presence of the two fuels. The study demonstrates that multienzyme MPC NP electrodes may improve the performance of biofuel cells by oxidizing mixtures of fuels in biomass. Mesoporous carbon nanoparticle electrodes for dual amperometric biosensors and multifuel-driven biofuel cells are reported. Electrically contacted bienzyme electrodes are prepared by the capping of different relays in mesoporous carbon nanoparticles through crosslinking of two different enzymes. The electrodes are implemented for the dual analysis of analytes and to construct biofuel cells that effectively utilize biomass fuel substrates.