3D Parylene sheath neural probe for chronic recordings
3D Parylene sheath neural probe for chronic recordings
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DOI：
10.1088/1741-2560/10/4/045002
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发表时间：
2013-08-01
影响因子：
4
通讯作者：
Meng, E.
中科院分区：
文献类型：
--
作者：
Kim, B. J.;Kuo, J. T. W.;Meng, E.
Objective.来自植入神经探针的可靠慢性记录仍然是一个重大挑战;当前的硅基和微丝技术经历了导致信号质量损失的各种生物和非生物故障模式。Approach.介绍了一种具有克服这些障碍潜力的多管齐下的替代策略，该策略将新型三维（3D）聚合物基探针结构与涂层相结合。具体而言，基于Parylene C鞘的神经探针涂覆有加载到基质胶载体上的神经营养和抗炎因子，以促进神经元过程的向内生长，从而改善记录质量，减少免疫反应，并促进改善探针整合到脑组织中，从而与其刚性对应物相比实现可靠的长期实施。主要结果。探头的3D护套结构通过表面微加工的Parylene C微通道的热成型形成，电极位点衬在管腔的内部和外部区域。通过循环伏安法和电化学阻抗谱进行电化学表征的探针，并表示合适的电极性能的神经记录（1 kHz的电阻抗类似于200 k Ω在体外）。开发了一种用于将顺应性聚合物探针插入神经组织的新型引入器工具，并在体外使用琼脂糖凝胶和在大鼠大脑皮层中进行了体内验证。通过将1 kHz电阻抗保持在功能范围内（
Objective. Reliable chronic recordings from implanted neural probes remain a significant challenge; current silicon-based and microwire technologies experience a wide range of biotic and abiotic failure modes contributing to loss of signal quality. Approach. A multi-prong alternative strategy with potential to overcome these hurdles is introduced that combines a novel three dimensional (3D), polymer-based probe structure with coatings. Specifically, the Parylene C sheath-based neural probe is coated with neurotrophic and anti-inflammatory factors loaded onto a Matrigel carrier to encourage the ingrowth of neuronal processes for improved recording quality, reduce the immune response, and promote improved probe integration into brain tissue for reliable, long-term implementation compared to its rigid counterparts. Main results. The 3D sheath structure of the probe was formed by thermal molding of a surface micromachined Parylene C microchannel, with electrode sites lining the interior and exterior regions of the lumen. Electrochemical characterization of the probes via cyclic voltammetry and electrochemical impedance spectroscopy was performed and indicated suitable electrode properties for neural recordings (1 kHz electrical impedance of similar to 200 k Omega in vitro). A novel introducer tool for the insertion of the compliant polymer probe into neural tissue was developed and validated both in vitro using agarose gel and in vivo in the rat cerebral cortex. In vivo electrical functionality of the Parylene C-based 3D probes and their suitability for recording the neuronal activity over a 28-day period was demonstrated by maintaining the 1 kHz electrical impedance within a functional range (