Solid-state nanopore based biomimetic voltage gated ion channels.
Solid-state nanopore based biomimetic voltage gated ion channels.
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基于固态纳米孔的仿生电压门控离子通道。
DOI：
10.1088/1748-3190/aa811b
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发表时间：
2017
影响因子：
3.4
通讯作者：
Theogarajan,Luke
中科院分区：
文献类型：
--
作者：
Pevarnik,Matthew;Cui,Weibin;Yemenicioglu,Sukru;Rofeh,Justin;Theogarajan,Luke
电压门控对神经元的计算能力至关重要。我们表明，这种效果可以在固态纳米孔中通过用氧化还原活性分子官能化孔内部来模拟。我们研究了一种活性生物分子-醌-整合到固态纳米孔中，及其随后的诱导电压门控。我们发现，电压门控效应模仿生物门控系统在其经典的S形电压响应，不同于以前的合成电压门控系统。最初，醌由于本体溶液中的自由基而经历还原，并转化为氢醌状态。在去质子化时，氢醌然后充当带电的纳米机械臂，其在施加的电势下打开通道。我们建立了醌获得一个单一的净电荷时，纳米孔内的pH值达到其pKa值，并探讨影响净pH值的因素，在中间的孔。通过理论、实验和模拟相结合的方法，我们得出结论，浓度极化和通道内pH值的变化是导致这种门控效应的主要原因。
Voltage gating is essential to the computational ability of neurons. We show this effect can be mimicked in a solid-state nanopore by functionalizing the pore interior with a redox active molecule. We study the integration of an active biological molecule—a quinone—into a solid state nanopore, and its subsequent induced voltage gating. We show that the voltage gating effect mimics biological gating systems in its classic sigmoidal voltage response, unlike previous synthetic voltage gating systems. Initially, the quinone undergoes a reduction due to radicals in the bulk solution, and is converted to the hydroquinone state. Upon deprontonation the hydroquinone then acts as a charged nanomechanical arm, which opens the channel under the applied potential. We establish that the quinone gains a single net charge when the pH inside of the nanopore reaches its pKa value, and explore factors that influence the net pH in the middle of the pore. Using a combination of theory, experiment and simulation, we conclude that concentration polarization and a shift of the pH inside of the channel is the main cause of this gating effect.