Tenure-Track Program for Innovative Research, University of Fukui, 910-8507, Japan.
Department of Frontier Fiber Technology and Science, Graduate School of Engineering, University of Fukui, 910-8507, Japan.
J Nanosci Nanotechnol. 2019 Jun 1;19(6):3551-3557. doi: 10.1166/jnn.2019.16121.
For increasing the output of biofuel cells, increasing the cooperation between enzyme reaction and electron transfer on the electrode surface is essential. Highly oriented immobilization of enzymes onto a carbon nanotube (CNT) with a large specific surface area and excellent conductivity would increase the potential for their application as biosensors and biofuel cells, by utilizing the electron transfer between the electrode-molecular layer. In this study, we prepared a CNT-enzyme complex with highly oriented immobilization of enzyme onto the CNT surface. The complex showed excellent electrical characteristics, and could be used to develop biodevices that enable efficient electron transfer. Multi-walled carbon nanotubes (MWCNT) were dispersed by pyrene butyric acid -hydroxysuccinimide ester, and then -(5-amino-1-carboxypentyl) iminodiacetic acid (AB-NTA) and NiCl₂ were added to modify the NTA-Ni complex on the CNT surface. Pyrroloquinoline quinone (PQQ)-dependent glucose dehydrogenase (GDH) was immobilized on the CNT surface through a genetically introduced His-tag. Formation of the MWCNT-enzyme complex was confirmed by monitoring the catalytic current electrochemically to indicate the enzymatic activity. PQQ-GDH was also immobilized onto a highly ordered pyrolytic graphite surface using a similar process, and the enzyme monolayer was visualized by atomic force microscopy to confirm its structural properties. A biofuel cell was constructed using the prepared CNT-enzyme complex and output evaluation was carried out. As a result, an output of 32 W/cm² could be obtained without mediators.
为了提高生物燃料电池的输出功率，增加酶反应和电子在电极表面的转移之间的协同作用至关重要。将具有大比表面积和优异导电性的碳纳米管（CNT）上的酶进行高度定向固定，将增加其作为生物传感器和生物燃料电池应用的潜力，利用电极-分子层之间的电子转移。在这项研究中，我们制备了一种 CNT-酶复合物，其中酶高度定向固定在 CNT 表面上。该复合物表现出优异的电特性，可用于开发能够实现高效电子转移的生物器件。多壁碳纳米管（MWCNT）通过芘丁酸-羟基琥珀酰亚胺酯分散，然后加入-(5-氨基-1-羧基戊基)亚氨基二乙酸（AB-NTA）和 NiCl₂，在 CNT 表面修饰 NTA-Ni 配合物。通过遗传引入 His 标签，将吡咯喹啉醌（PQQ）依赖性葡萄糖脱氢酶（GDH）固定在 CNT 表面上。通过电化学监测催化电流来确认 MWCNT-酶复合物的形成，以指示酶的活性。使用类似的过程，将 PQQ-GDH 也固定在高度有序的热解石墨表面上，并通过原子力显微镜观察酶单层以确认其结构特性。使用制备的 CNT-酶复合物构建了生物燃料电池，并进行了输出评估。结果，在没有介体的情况下可以获得 32 W/cm²的输出。
