Department of Material Science and Electrical Engineering, Center for Physical Sciences and Technology, Saulėtekio av. 3, Vilnius, LT-10257, Lithuania.
Phys Chem Chem Phys. 2019 Feb 6;21(6):2968-2976. doi: 10.1039/c8cp07233g.
In this work, a general theoretical and numerical approach based on semiconductor theory, which could be applied to a study of direct enzyme wiring, has been discussed. Marcus-Hush theory was applied to evaluate the potential transfer of charge carriers (holes and electrons) between glucose oxidase (GOx) and organic semiconductors. Two mechanisms of multistep hopping of charge to/from the oxidised/reduced flavin-based moiety through residues of aromatic amino acids located in GOx and long range charge direct tunnelling from the cofactor to the organic semiconductor surface have been proposed and evaluated. It was determined that the hole-hopping mechanism is possible and proceeds at a low ionization potential of the organic semiconductor. The calculations reveal that hopping of electrons is blocked, but direct electron tunnelling between the cofactor and the organic semiconductor is still probable. The most optimal conditions and tunable characteristics of GOx-based biosensors such as the ionization potential, electron affinity of organic semiconductors and distance between the enzyme and surface were estimated for the first time.
本文讨论了一种基于半导体理论的通用理论和数值方法，该方法可应用于直接酶接线的研究。Marcus-Hush 理论被应用于评估葡萄糖氧化酶（GOx）和有机半导体之间载流子（空穴和电子）的潜在转移。提出并评估了两种通过位于 GOx 中的芳香族氨基酸残基从氧化/还原黄素基部分多步骤跳跃电荷到/来自有机半导体的机制，以及从辅因子到有机半导体表面的长程电荷直接隧穿。确定了空穴跳跃机制是可能的，并且在有机半导体的低电离势下进行。计算表明，电子的跳跃被阻止，但辅酶和有机半导体之间的直接电子隧穿仍然可能。首次估计了基于 GOx 的生物传感器的最佳条件和可调特性，例如有机半导体的电离势、电子亲和力以及酶和表面之间的距离。
