3D Semiconducting Polymer/Graphene Networks: Toward\nSensitive Photocathodic Enzymatic Bioanalysis

Abstract

This\nwork reports the development of three-dimensional (3D) semiconducting\npolymer/graphene (SP/G) networks toward sensitive photocathodic enzymatic\nbioanalysis. Specifically, the porous 3D graphene was first synthesized\nvia the hydrothermal and freeze-dry processes and then mixed with\nsemiconducting polymer to obtain the designed hierarchical structure\nwith unique porosity and large surface area. Afterward, the as-prepared\nhybrid was immobilized onto the indium tin oxide (ITO) for further\ncharacterizations. Exemplified by sarcosine oxidase (SOx) as a model\nbiocatalyst, an innovative 3D SP/G-based photocathodic bioanalysis\ncapable of sensitive and specific sarcosine detection was achieved.\nThe suppression of cathodic photocurrent was observed in the as-developed\nphotocathodic enzymatic biosystem due to the competition of oxygen\nconsumption between the enzyme–biocatalyst process and O₂-dependent photocathodic electrode. This work not only presented\na unique protocol for 3D SP/G-based photocathodic enzymatic bioanalysis\nbut also provided a new horizon for the design, development, and utilization\nof numerous 3D platforms in the broad field of general photoelectrochemical\n(PEC) bioanalysis.