Center of Excellence for Trace Analysis and Biosensor, Prince of Songkla University, Hat Yai 90110, Thailand.
Division of Physical Science, Faculty of Science, Prince of Songkla University, Hat Yai 90110, Thailand.
Int J Mol Sci. 2023 Feb 28;24(5):4657. doi: 10.3390/ijms24054657.
Glucose oxidase (GOx)-based electrodes are important for bioelectronics, such as glucose sensors. It is challenging to effectively link GOx with nanomaterial-modified electrodes while preserving enzyme activity in a biocompatible environment. To date, no reports have used biocompatible food-based materials, such as egg white proteins, combined with GOx, redox molecules, and nanoparticles to create the biorecognition layer for biosensors and biofuel cells. This article demonstrates the interface of GOx integrated with egg white proteins on a 5 nm gold nanoparticle (AuNP) functionalized with a 1,4-naphthoquinone (NQ) and conjugated with a screen-printed flexible conductive carbon nanotube (CNT)-modified electrode. Egg white proteins containing ovalbumin can form three-dimensional scaffolds to accommodate immobilized enzymes and adjust the analytical performance. The structure of this biointerface prevents the escape of enzymes and provides a suitable microenvironment for the effective reaction. The bioelectrode's performance and kinetics were evaluated. Using redox-mediated molecules with the AuNPs and the three-dimensional matrix made of egg white proteins improves the transfer of electrons between the electrode and the redox center. By engineering the layer of egg white proteins on the GOx-NQ-AuNPs-mediated CNT-functionalized electrodes, we can modulate analytical performances such as sensitivity and linear range. The bioelectrodes demonstrate high sensitivity and can prolong the stability by more than 85% after 6 h of continuous operation. The use of food-based proteins with redox molecule-modified AuNPs and printed electrodes demonstrates advantages for biosensors and energy devices due to their small size, large surface area, and ease of modification. This concept holds a promise for creating biocompatible electrodes for biosensors and self-sustaining energy devices.
葡萄糖氧化酶(GOx)基电极在生物电子学中很重要,例如葡萄糖传感器。在生物相容性环境中有效地将 GOx 与纳米材料修饰的电极连接,同时保持酶的活性,这是具有挑战性的。迄今为止,尚无报道使用生物相容性的基于食品的材料,例如蛋清蛋白,与 GOx、氧化还原分子和纳米颗粒结合,为生物传感器和生物燃料电池创建生物识别层。本文展示了在 5nm 金纳米粒子(AuNP)上集成 GOx 与蛋清蛋白的界面,该 AuNP 用 1,4-萘醌(NQ)功能化,并与丝网印刷的柔性导电碳纳米管(CNT)修饰电极共轭。含有卵白蛋白的蛋清蛋白可以形成三维支架,以容纳固定化酶并调整分析性能。该生物界面的结构可防止酶逃逸,并为有效反应提供合适的微环境。评估了该生物电极的性能和动力学。使用具有 AuNPs 的氧化还原介导分子和由蛋清蛋白制成的三维基质可改善电极和氧化还原中心之间的电子转移。通过在 GOx-NQ-AuNPs 介导的 CNT 修饰电极上工程化蛋清蛋白层,可以调节分析性能,如灵敏度和线性范围。生物电极具有高灵敏度,并且在连续运行 6 小时后可以将稳定性延长超过 85%。基于具有氧化还原分子修饰的 AuNPs 和印刷电极的食品基蛋白的使用,由于其尺寸小、表面积大且易于修饰,为生物传感器和能量器件展示了优势。该概念为生物传感器和自维持能量器件创造了生物相容性电极的前景。