Department of Life and Health 'V. Tiberio', University of Molise, Campobasso, Italy. IRCCS Neuromed, Via Atinense 18, 86077, Pozzilli (IS), Italy. These authors contributed equally. Author to whom any correspondence should be addressed.
J Neural Eng. 2020 Jul 3;17(3):036032. doi: 10.1088/1741-2552/ab98db.
The development of electrode arrays able to reliably record brain electrical activity is a critical issue in brain machine interface (BMI) technology. In the present study we undertook a comprehensive physico-chemical, physiological, histological and immunohistochemical characterization of new single-walled carbon nanotubes (SWCNT)-based electrode arrays grafted onto medium-density polyethylene (MD-PE) films.
The long-term electrical stability, flexibility, and biocompatibility of the SWCNT arrays were investigated in vivo in laboratory rats by two-months recording and analysis of subdural electrocorticogram (ECoG). Ex-vivo characterization of a thin flexible and single probe SWCNT/polymer electrode is also provided.
The SWCNT arrays were able to capture high quality and very stable ECoG signals across 8 weeks. The histological and immunohistochemical analyses demonstrated that SWCNT arrays show promising biocompatibility properties and may be used in chronic conditions. The SWCNT-based arrays are flexible and stretchable, providing low electrode-tissue impedance, and, therefore, high compliance with the irregular topography of the cortical surface. Finally, reliable evoked synaptic local field potentials in rat brain slices were recorded using a special SWCNT-polymer-based flexible electrode.
The results demonstrate that the SWCNT arrays grafted in MD-PE are suitable for manufacturing flexible devices for subdural ECoG recording and might represent promising candidates for long-term neural implants for epilepsy monitoring or neuroprosthetic BMI.
开发能够可靠记录脑电活动的电极阵列是脑机接口（BMI）技术的关键问题。在本研究中，我们对新的单壁碳纳米管（SWCNT）基电极阵列进行了全面的物理化学、生理、组织学和免疫组织化学表征，这些电极阵列被接枝到中密度聚乙烯（MD-PE）薄膜上。
通过实验室大鼠两个月的硬膜下脑电图（ECoG）记录和分析，研究了 SWCNT 阵列的长期电稳定性、柔韧性和生物相容性。还提供了一种薄而灵活的单探头 SWCNT/聚合物电极的体外特性。
SWCNT 阵列能够在 8 周内捕获高质量且非常稳定的 ECoG 信号。组织学和免疫组织化学分析表明，SWCNT 阵列具有良好的生物相容性，可以用于慢性疾病。基于 SWCNT 的阵列具有柔韧性和可拉伸性，提供低电极-组织阻抗，因此与皮质表面的不规则形貌高度兼容。最后，使用特殊的 SWCNT-聚合物基柔性电极记录了大鼠脑片可靠的诱发性突触局部场电位。
结果表明，接枝在 MD-PE 上的 SWCNT 阵列适合制造用于硬膜下 ECoG 记录的柔性器件，可能是癫痫监测或神经假体 BMI 的长期神经植入物的有前途的候选物。
