Significant enhancement of direct electric communication across enzyme-electrode interface via nano-patterning of synthetic glucose dehydrogenase on spatially tunable gold nanoparticle (AuNP)-modified electrode

In this study, the effect of inter-enzyme steric hindrance that occurs during enzyme immobilization on the electrode, on direct electrical communications of enzyme with electrode was investigated via nano-patterning of enzymes on the electrode. Here, the nano-patterning of enzymes was achieved through the combination of DET-capable enzyme that was produced via fusion of site-specific gold binding peptide (GBP) to catalytic subunit of enzyme and gold nanoparticle (AuNP) array with highly tunable dimensions of AuNPs, resulting in spatially controllable enzyme-electrode. The nano-scale spatial control between immobilized enzymes on the highly tuned AuNPs shows different DET efficiency across the enzyme-electrode interface, showing 18.47% of maximum electron recovery which is 3.2-fold enhanced electron recovery efficiency compared to spatially non-controlled enzymes on the electrode where showed 5.7% of electron recovery. The result affirms that inter-enzyme interaction is a significant parameter that decides the enzyme-electrode performance. [Display omitted] •The fusion of GBP to the catalytic subunit of GDH enabled interfacial DET in the enzyme-electrode.•The effect of inter-enzyme agglomeration on efficiency of interfacial DET was investigated, related to its effect on Rct.•The enzyme nano-patterning was developed via combination of synthetic enzyme and AuNP-modified electrode.•The nano-scale spatial control of synthetic GDHs on the electrode enhanced electroactive coverage of enzyme-electrode.•The inter-enzyme agglomeration is the important parameter to consider for the development of DET-based bioelectronics.