Nanothin ferrocene film plasma polymerized over physisorbed glucose oxidase: High-throughput fabrication of bioelectronic devices without chemical modifications

We describe a method for creating a mediator-containing interface between an enzyme and an electrode, achieving simpler and more reliable immobilization of the enzyme with the enhanced detection sensitivity. A nanothin polymer film containing a redox mediator, made of dimethylaminomethylferrocene, was plasma-deposited directly onto a glucose oxidase-physisorbed electrode, with which a relevant bioelectrochemical signal was observed without prior or further chemical modification of the enzyme molecules. The results of the surface characterizations before and after the enzyme immobilization showed that this method gave control over the spatial orientation of single enzyme molecules in favor of efficient and reproducible signal generation. Considering that the film deposition was performed using microfabrication-compatible organic plasma, our new method has a great potential of enabling high-throughput production of bioelectronic devices without chemical modification steps.