Biological Assembly of Enzyme Electrodes for Biofuel Cells

[33672]生物燃料电池提供了一种环保、可持续的发电方法。然而，迄今为止实现的低功率密度限制了它们的适用性。本研究旨在通过控制酶催化剂在燃料电池电极上的组装来提高生物燃料电池的功率密度。为了实现这一目标，提出的研究旨在改善氧化还原蛋白和导电载体之间的电接触，并创建旨在实现更高功率输出的电极结构。组装过程是分层的，其中纳米尺寸的蛋白质被模板化为近微米尺寸的病毒，然后自组装成宏观电极结构。该模型系统将重点关注葡萄糖，一种可再生原料，作为电力生产的燃料来源。研究计划有两个主要目标。第一个目标是创建基于将酶与无机成分组装成一个整体结构的病毒模板酶电极。设计了异功能M13病毒，通过选择性肽结合将葡萄糖氧化酶偶联到金纳米线上，以实现葡萄糖氧化酶氧化还原中心和电极之间的介导电子转移。提出了三种酶电极结构，以克服在氧化还原蛋白和导电载体之间建立电接触的局限性。第二个目标是利用M13病毒的液晶特性将这些模板酶电极结构自组装成坚固的电极结构。这种方法寻求获得至少10微米厚度的电极，这些电极密集地包裹着酶，但具有可控制的孔隙度，以便电解质可接近。这种电极设计的潜力，以实现更高水平的功率密度，通过增加电线酶的密度，并确保燃料接近电极将被评估。更广泛的影响教育和推广计划以拟议的研究活动为基础。本科生和研究生将接受生物工程、电化学和纳米材料的跨学科培训。来自代表性不足群体的本科生将通过加州大学洛杉矶分校（UCLA）现有的项目被招募参加拟议的研究。与加州纳米系统研究所（CNSI）合作，将为高中教师开发生物燃料电池工具包和教学视频，作为将可再生能源主题引入洛杉矶联合学区高中科学课程的一种方式。

1033672HuangIntellectual MeritBiofuel cells provide an environmentally benign, sustainable method for electricity production. However, the low power densities achieved to date limit their applicability. This proposed research seeks to improve the power density of biological fuel cells through controlled assembly of enzyme catalysts onto the fuel cell electrode. To achieve this goal, the proposed research seeks to improve electrical contact between the redox proteins and the conductive support, and to create electrode architectures which are designed to achieve higher power output. The assembly process is hierarchical, where proteins of nanometer dimensions are templated into viruses of nearly micron size which then self-assemble into macroscopic electrode structures. The model system will focus on glucose, a renewable feedstock, as the fuel source for electricity production. The research plan has two major objectives. The first objective is to create virus-templated enzyme electrodes which are based on assembling enzymes with inorganic constituents into an integrated structure. The heterofunctional M13 virus is designed to couple glucose oxidase to a gold nanowire through selective peptide binding to achieve mediated electron transfer between the redox center of the glucose oxidase and the electrode. The three enzyme electrode structures are proposed to overcome the limitations experienced in establishing electrical contact between the redox protein and the conductive support. The second objective is to use the liquid crystal nature of the M13 virus to self-assemble these templated enzyme electrode structures into robust electrode architectures. This approach seeks to obtain electrodes of least 10 micron thickness that are densely packed with enzymes but possess controlled porosity for electrolyte accessibility. The potential of this electrode design to achieve higher levels of power density by increasing the density of electrically-wired enzymes and ensuring accessibility of the fuel to the electrode will be assessed.Broader ImpactsThe education and outreach plan is based on the proposed research activities. Undergraduate and graduate students will receive cross-disciplinary training in bioengineering, electrochemistry, and nanomaterials. Undergraduate students from underrepresented groups will be recruited through existing programs at the University of California at Los Angeles (UCLA) to participate in the proposed research. In collaboration with California NanoSystems Institute (CNSI), biofuel cell kits and instructional videos will be developed for high school teachers as a way of bringing renewable energy topics to the high school science curriculum of the Los Angeles Unified School District.