Biosensors and Bioelectronics Centre, Division of Sensor and Actuator Systems, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
Biosensors and Bioelectronics Centre, Division of Sensor and Actuator Systems, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
Biosens Bioelectron. 2018 Nov 30;120:115-121. doi: 10.1016/j.bios.2018.08.017. Epub 2018 Aug 10.
Poly(ethylenedioxythiophene) (PEDOT) has attracted considerable attention as an advanced electrode material for electrochemical sensors and biosensors, due to its unique electrical and physicochemical properties. Here, we demonstrate the facile preparation of a positively-charged and hierarchical micro-structured PEDOT electrochemical interface with enhanced electrode kinetics for the electrooxidation of NADH. Processable PEDOT colloidal microparticles (PEDOT CMs) were synthesised by template-assisted polymerisation and were then utilised as building blocks for the fabrication of hierarchically-structured electrodes with a larger accessible electroactive surface (2.8 times larger than that of the benchmark PEDOT:PSS) and inter-particle space, thus improving electrode kinetics. The intrinsic positive charge of the PEDOT CMs further facilitated the detection of negatively-charged molecules by electrostatic accumulation. Due to the synergistic effect, these hierarchically-structured PEDOT CMs electrodes exhibited improved NADH electrooxidation at lower potentials and enhanced electrocatalytic activity compared to the compact structure of conventional PEDOT:PSS electrodes. The PEDOT CMs electrodes detected NADH over the range of 20-240 μM, with a sensitivity of 0.0156 μA/μM and a limit of detection of 5.3 μM. Moreover, the PEDOT CMs electrode exhibited a larger peak separation from the interferent ascorbic acid, and improved stability. This enhanced analytical performance for NADH provides a sound basis for further work coupling to a range of NAD-dependent dehydrogenases for applications in biosensing, bio-fuel cells and biocatalysis.
聚（3,4-乙烯二氧噻吩）（PEDOT）因其独特的电学和物理化学性质，作为电化学传感器和生物传感器的先进电极材料引起了相当大的关注。在这里，我们展示了一种简便的方法，可制备带正电荷的分层微结构 PEDOT 电化学界面，从而增强电极动力学，促进 NADH 的电氧化。可加工的 PEDOT 胶体微球（PEDOT CMs）通过模板辅助聚合合成，然后用作制造具有更大可及电活性表面（比基准 PEDOT：PSS 大 2.8 倍）和颗粒间空间的分层结构电极的构建块，从而改善电极动力学。PEDOT CMs 的固有正电荷进一步促进了带负电荷的分子通过静电积累进行检测。由于协同效应，与传统的 PEDOT：PSS 电极的紧密结构相比，这些分层结构的 PEDOT CMs 电极在较低的电势下表现出改善的 NADH 电氧化和增强的电催化活性。PEDOT CMs 电极在 20-240 μM 的范围内检测 NADH，灵敏度为 0.0156 μA/μM，检测限为 5.3 μM。此外，PEDOT CMs 电极的峰与干扰物抗坏血酸的分离更大，并且稳定性更好。这种对 NADH 的增强分析性能为进一步与一系列 NAD 依赖性脱氢酶结合以应用于生物传感、生物燃料电池和生物催化提供了良好的基础。
