Neural Electrodes with Enhanced Charge Injection and Reduced Interfacial Impedance Using Graphenated Carbon Nanotubes Coated With Atomic Layer-Deposited Platinum Nanoparticles

本项目的目的是评价石墨化碳纳米管(GCNTs)的低阻抗性能， 用于神经刺激的较小电极，使用脑深部刺激(DBS)作为测试案例，具有长期 目标是开发一种阻抗更低、尺寸更小的新型神经电极。较低的阻抗 电极-组织界面导致较低的功率消耗，因为需要较小的电压来实现 同样的电荷注入。更低的功耗延长了电池寿命，并减小了 电池，因此植入的装置。刺激电极的最小尺寸受 有效刺激所需的最小电荷注入。同样，电极的大小也是一个重要的因素 电极插入所造成的插入损伤的因素以及可以 受到刺激。更低的阻抗，更小的电极将导致更少的损害电极和组合 更小、更持久的电池。我们将把gCNT电极的性能与标准电极进行比较 铂电极使用定量的体外和体内测量。我们预计将增加可逆性 与相同尺寸的铂电极相比，充电注入容量降低了20倍，阻抗降低了65%。这个 本项目的具体目标是：(1)量化gCNT形态对电荷注入、界面 阻抗和附着力，并确定改善这些性能的工艺条件。(2)按金 铂纳米粒子通过原子层沉积(ALD)在碳纳米管上进一步增加电荷注入 容量和降低阻抗。这些铂-gCNT将以棋盘图案(平衡铂 多电极阵列(MEA)上的电极)，允许在动物体内进行性能比较(3)。测试 丘脑底核内植入电极的偏侧帕金森病6-羟多巴胺损毁大鼠体内MEAs 并提供慢性每日缓解症状的DBS，以评估铂-gCNT与铂电极的性能。 申请人认为，拟议的研究是创新的，因为它引入了一种新材料(GCNTs)和一种 将改善神经电极性能的新工艺(ALD)。预计gCNTs将具有 比标准铂电极的性能要好得多。ALD有能力将纳米颗粒沉积在 一种使涂覆的gCNTs表面积和电化学表面积最大化的独特方法 铂的表面积。纳米铂将用于进一步增强gCNTs的神经电极 性能。该项目的结果将是对铂-gCNTs进行高效的全面评估 神经刺激电极。如果实现，它将导致神经刺激电极变得更小，限制 插入损坏，功耗更低，从而减小了电池的尺寸，延长了电池的使用寿命 并可能扩展可能的电极系统的前沿。

The objective of this project is to evaluate graphenated carbon nanotubes (gCNTs) as lower impedance, smaller electrodes for neurostimulation, using deep brain stimulation (DBS) as a test case, with the long-term goal of developing a new type of neural electrode with lower impedance and smaller size. Lower impedance of the electrode-tissue interface results in lower power consumption, as a smaller voltage is required to achieve the same charge injection. Lower power consumption extends battery life and decreases the size of the batteries and thus of the implanted device. The minimum size of stimulating electrodes is limited by the minimum charge injection required for effective stimulation. As well, the size of the electrode is an important factor in the insertion damage created by electrode insertion and the specificity of the volume that can be stimulated. Lower impendence, smaller electrodes will lead to less damaging electrodes and a combination of smaller and longer lasting batteries. We will compare the performance of gCNT electrodes to standard platinum electrodes using quantitative in vitro and in vivo measurements. We expect to increase the reversible charge injection capacity by 20x and reduce the impedance by 65% versus the same-sized Pt electrode. The specific aims of this project are: (1) Quantify the effect of gCNT morphology on charge injection, interfacial impedance, and adhesion and identify processing conditions that improve these properties. (2) Deposit platinum nanoparticles via atomic layer deposition (ALD) on gCNTs to further increase the charge injection capacity and decrease impedance. These Pt-gCNTs will be deposited in a checkerboard pattern (balance Pt electrodes) on a multielectrode array (MEA), allowing performance to be compared within animal (3). Test the MEAs in vivo in hemiparkinsonian 6-OHDa lesioned rats, implanting electrodes into the subthalamic nucleus and delivering chronic daily symptom-relieving DBS in order to assess Pt-gCNT vs Pt electrode performance. In the applicant’s opinion, proposed research is innovative because it introduces a new material (gCNTs) and a new process (ALD) that will improve the performance of neural electrodes. gCNTs are expected to have significantly better performance than standard Pt electrodes. ALD has the capability to deposit nanoparticles in a unique way that maximizes the amount of gCNTs surface area that is coated as well as the electrochemical surface area of the platinum. Nanostructured platinum will be used to further enhance gCNTs’ neural electrode performance. The outcome of this project will be a comprehensive assessment of Pt-gCNTs as highly efficient neural stimulation electrodes. If realized, it will lead to neural stimulation electrodes that are smaller, limiting insertion damage, and consume less power, thereby reducing the size and increasing the lifetime of batteries and may expand the frontier of possible electrode systems.