Department of Polymer Science and Engineering, MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Key Laboratory of Adsorption and Separation Materials & Technologies of Zhejiang Province, Zhejiang University, Hangzhou, 310027, China.
School of Medicine, Hangzhou Normal University, Hangzhou, 311121, China.
Biosens Bioelectron. 2020 Mar 15;152:112001. doi: 10.1016/j.bios.2019.112001. Epub 2019 Dec 28.
In this study, we developed a convenient way to construct a flexible enzymatic electrode with excellent stability and electrochemical performance for implanted glucose monitoring. The electrode was constructed through the co-immobilization of the glucose oxidase micro-particles (GOD MPs) and multi-wall carbon nanotubes (CNT) on the inner surface of a gradient-structured hollow fiber membrane (GHM), where CNT improved the electron transport efficiency and GHM controlled the transfer of substances and interferences. GOD MPs showed higher stability under various operation conditions than the free enzymes due to the MnCO template method, which enabled the biosensor to remain relative sensitivity at >86% over 9 days. The GOD MPs biosensor also showed high selectivity, reproducibility, and linear sensing range from 0 mM to 24 mM (R = 0.9993) with a current sensitivity of 25 nA/mM. The combination of porous-structured membrane and the flexible CNT meshes ensures the electrical connections and sensing accuracy of the biosensor under the deformation status. In-vivo experiments showed reliable current responses to variations in blood glucose concentrations that were consistent with tail blood test results. This co-immobilization of enzyme micro-particles in the 3D porous structure method developed a bio-composite platform technology towards the applications in flexible sensing and implantable medical devices.
在这项研究中，我们开发了一种方便的方法来构建具有优异稳定性和电化学性能的灵活酶电极，用于植入式葡萄糖监测。该电极通过将葡萄糖氧化酶微颗粒 (GOD MPs) 和多壁碳纳米管 (CNT) 共同固定在梯度结构中空纤维膜 (GHM) 的内表面上来构建，其中 CNT 提高了电子传输效率，而 GHM 控制了物质和干扰的传递。由于 MnCO 模板法，GOD MPs 在各种操作条件下表现出更高的稳定性，这使得生物传感器在 9 天内仍保持相对灵敏度>86%。GOD MPs 生物传感器还表现出高选择性、重现性和线性传感范围从 0 mM 到 24 mM（R = 0.9993），电流灵敏度为 25 nA/mM。多孔结构膜和灵活的 CNT 网格的组合确保了生物传感器在变形状态下的电连接和传感准确性。体内实验表明，对血糖浓度变化的可靠电流响应与尾血测试结果一致。这种在 3D 多孔结构中共同固定酶微颗粒的方法开发了一种生物复合材料平台技术，可应用于灵活的传感和植入式医疗设备。
