In vivo studies of polypyrrole/peptide coated neural probes
In vivo studies of polypyrrole/peptide coated neural probes
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DOI：
10.1016/s0142-9612(02)00415-5
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发表时间：
2003-02-01
期刊：
影响因子：
14
通讯作者：
Martin, DC
中科院分区：
文献类型：
--
作者：
Cui, XY;Wiler, J;Martin, DC
神经探针是微机械加工的多通道电极阵列，其促进外周和中枢神经系统中的神经元的功能刺激和记录。为了长期的预防。表面修饰对于维持电极和神经元之间的稳定连接是必要的。采用电化学聚合法将导电聚合物聚吡咯（PPy）和合成肽DCDPGYIGSR共沉积在电极表面。在浸泡实验中测试了PPy/ DCDPGYIGSR涂层的稳定性。发现肽被捕获在PPy膜中，并且在DI水中浸泡7周内没有扩散开。将涂覆的探针植入豚鼠脑中，持续1、2和3周。进行记录测试并监测阻抗。用免疫细胞化学方法对标记的探针和组织进行检测。在涂层电极上发现明显更多的神经丝阳性染色，这表明涂层与体内神经元结构建立了牢固的连接。从附着有神经元的包被部位获得良好的记录。第一周组织切片没有明显的神经胶质增生。在第2周，在探针轨道或涂覆的和未涂覆的探针周围形成主要由脑膜成纤维细胞和至少包括纤连蛋白的ECM蛋白组成的非神经元组织层。第三周末，星形胶质细胞开始形成松散的组织层。(C)2002爱思唯尔科技有限公司版权所有。
Neural probes are micromachined multichannel electrode arrays that facilitate the functional stimulation and recording of neurons in the peripheral and central nervous system. For long-term implantations. surface modification is necessary for maintaining the stable connection between electrodes and neurons. The conductive polymer polypyrrole (PPy) and synthetic peptide DCDPGYIGSR were co-deposited on the electrode surface by electrochemical polymerization. The stability of PPy/ DCDPGYIGSR coatings was tested in soaking experiments. It was found that the peptide was entrapped in the PPy film and did not diffuse away within 7 weeks of soaking in DI water. Coated probes were implanted in guinea pig brain for periods of 1, 2 and 3 weeks. Recording tests were performed and the impedance was monitored. The explanted probes and tissue were examined by iumunocytochemical studies. Significantly more neurofilament positive staining was found on the coated electrode which indicated that the coatings had established strong connections with the neuronal structure in vivo. Good recordings were obtained from the coated sites that had neurons attached. First week tissue sections had no significant gliosis. In week 2, a layer of non-neuronal tissue consisting of mostly meningeal fibroblasts and ECM protein including at least fibronectin was formed around the probe tracks or both coated and uncoated probes. Astrocytes started to form a loosely organized layer by the end of the third week. (C) 2002 Elsevier Science Ltd. All rights reserved.