...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nanotechnology >Empirical study of unipolar and bipolar configurations using high resolution single multi-walled carbon nanotube electrodes for electrophysiological probing of electrically excitable cells
【24h】

Empirical study of unipolar and bipolar configurations using high resolution single multi-walled carbon nanotube electrodes for electrophysiological probing of electrically excitable cells

机译：使用高分辨率单个多壁碳纳米管电极对电兴奋性细胞进行电生理探测的单极和双极配置的实证研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Identifying the neurophysiological basis underlying learning and memory in the mammalian central nervous system requires the development of biocompatible, high resolution, low electrode impedance electrophysiological probes; however, physically, electrode impedance will always be finite and, at times, large. Herein, we demonstrate through experiments performed on frog sartorius muscle that single multi-walled carbon nanotube electrode (sMWNT electrode) geometry and placement are two degrees of freedom that can improve biocompatibility of the probe and counteract the detrimental effects of MWNT/electrolyte interface impedance on the stimulation efficiency and signal-to-noise ratio (SNR). We show that high aspect ratio dependent electric field enhancement at the MWNT tip can boost stimulation efficiency. Derivation of the sMWNT electrode's electrical equivalent indicates that, at low stimulus voltage regimes below 1 V, current conduction is mediated by charge fluctuation in the double layer obviating electrolysis of water, which is potentially toxic to pH sensitive biological tissue. Despite the accompanying increase in electrode impedance, a pair of closely spaced sMWNT electrodes in a two probe (bipolar) configuration maintains biocompatibility and enhances stimulation efficiency and SNR compared to the single probe (unipolar) configuration. For stimulus voltages below 1 V, the electrical equivalent verifies that current conduction in the two probe configuration still proceeds via charge fluctuation in the double layer. As an extracellular stimulation electrode, the two sMWNT electrodes comprise a current dipole that concentrates the electric field and the current density in a smaller region of sartorius; consequently, the bipolar configuration can elicit muscle fiber twitching at low voltages that preclude electrolysis of water. When recording field potentials, the bipolar configuration subtracts the potential between two points allowing for the detection of higher signal amplitudes. As a result, SNR is improved. These results indicate that use of the high aspect ratio MWNT in a bipolar configuration can achieve a biocompatible electrode that offers enhanced stimulation efficiency and higher SNR.
机译：识别哺乳动物中枢神经系统中学习和记忆的神经生理基础需要开发生物相容，高分辨率，低电极阻抗的电生理探针。然而，从物理上讲，电极阻抗始终是有限的，有时甚至很大。在这里，我们通过对蛙类赛多利斯肌进行的实验证明，单个多壁碳纳米管电极（sMWNT电极）的几何形状和位置是两个自由度，可以改善探针的生物相容性并抵消MWNT /电解质界面阻抗对电极的不利影响刺激效率和信噪比（SNR）。我们表明，MWNT尖端的高纵横比依赖性电场增强可以提高刺激效率。 sMWNT电极的电当量推导表明，在低于1 V的低激励电压下，电流传导是由双层中的电荷波动介导的，从而避免了水的电解，而电解对pH敏感的生物组织可能具有毒性。尽管伴随着电极阻抗的增加，但是与单探针（单极）配置相比，两个探针（双极）配置中的一对紧密间隔的sMWNT电极可保持生物相容性并增强刺激效率和SNR。对于低于1 V的激励电压，电气等效值可验证两个探针配置中的电流传导仍会通过双层中的电荷波动而继续进行。作为细胞外刺激电极，两个sMWNT电极包括一个电流偶极子，该电场将电场和电流密度集中在较小的sartorius区域中。因此，双极型配置可在低电压下引起肌肉纤维抽搐，从而阻止水的电解。在记录场电势时，双极配置会减去两点之间的电势，从而可以检测到更高的信号幅度。结果，改善了SNR。这些结果表明，在双极性配置中使用高长宽比的MWNT可以实现生物相容性电极，从而提供增强的刺激效率和更高的SNR。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号