Conductive Polymer Recording and Stimulation Electrodes

描述(由申请人提供)：建议开发用于增强神经假体和基于电刺激的治疗中的电极的记录和刺激能力的涂层。这种涂层是以导电聚合物为基础的，我们最近发现，这种聚合物支持的电荷注入水平至少是目前可用的最高电荷注入容量材料的六倍。在聚合物与金属电极的粘合方面提出了具体的创新，并开发了具有生物活性的聚合物以增强和稳定电极-神经界面。第一阶段的主要目标是：1)开发将聚合物涂层牢固地附着在金属微电极表面的方法；2)在一个简短的长期研究中，评估聚合物涂层电极的被动和功能性生物兼容性。将使用几种附着力促进策略对沉积在金属电极上的聚合物的附着力、电荷注入能力和阻抗进行体外研究。在70天的体内研究中，附着的聚合物涂层将与穿透微电极一起用于组织学和功能生物相容性评估。电极的记录能力将每周监测一次。聚合物涂层电极将受到电荷注入挑战，其最大可能是目前材料的四倍。在体内，电流脉冲过程中的电特性以及对非固缩神经元密度和胶质包被程度的定量组织学评估将被用作稳定性和生物相容性的衡量标准。商业：EIC实验室将通过提供电极涂层服务、开发交钥匙电沉积系统以及通过许可将该技术商业化。相关：导电聚合物涂层的应用包括用于脊髓损伤的皮质控制假体(脑机接口)、用于视网膜色素变性或老年性黄斑变性患者的视网膜假体、用于盲人和聋人的皮质内视听假体、用于脊髓损伤的周围神经假体以及用于脑深部刺激(DBS)和心脏起搏等刺激疗法的电极。神经假体正被开发用于脊髓损伤、中风和与疾病相关的感觉缺陷的康复。基于电刺激的疗法正在开发中，用于治疗神经退行性疾病，如特发性震颤和帕金森氏症，以及癫痫、抑郁症和饮食失调的治疗。其中许多应用涉及到与神经系统的直接接口，并且需要具有记录和刺激能力的小面积电极，而不是贵金属。这项建议致力于开发导电聚合物的电聚合薄膜作为电极涂层，以满足这些假体和治疗中使用的电极的记录和刺激需求。与竞争电极涂层相比，导电聚合物的潜在优势是极高的电荷注入能力，以及开发包含生物活性分子的涂层的可能性，以促进稳定和功能增强的神经电极界面的形成。

DESCRIPTION (provided by applicant): The development of coatings for enhancing the recording and stimulation capabilities of electrodes used in neural prostheses and electrical stimulation based therapies is proposed. The coatings are based on conducting polymers that we have recently found support charge- injection levels at least six times greater than is possible with the highest charge-injection capacity materials presently available. Specific innovations in terms of polymer adhesion to metal electrodes and the development of polymers functionalized with biologically active species for enhancing and stabilizing the electrode-nerve interface are proposed. The principal Phase I objectives are 1) to develop methods for the robust attachment of the polymer coatings to the surface of metal microelectrodes and 2) to evaluate, in a short chronic study, the passive and functional biocompatibility of polymer-coated electrodes. In vitro studies of the adhesion, charge-injection capabilities and impedance of polymers deposited on metal electrodes using several adhesion promoting strategies will be undertaken. Adherent polymer coatings will be used with penetrating microelectrodes for histologic and functional biocompatibility assessments in a 70 day in vivo study. The recording capabilities of the electrodes will be monitored weekly. Polymer-coated electrodes will be subjected to a charge-injection challenge at four times the maximum possible with present materials. In vivo electrical characteristics during current pulsing and quantitative histologic evaluation of non-pyknotic neuron densities and the extent of gliotic encapsulation will be used as measures of stability and biocompatibility. Commercial: EIC Laboratories will commercialize the technology by offering electrode coating services, the development of turn-key electrodeposition systems, and through licensing. Relevance: Applications of the conducting polymer coatings include cortical control prostheses (brain-machine interfaces) for the spinal cord injured, retinal prostheses for patients with retinitis pigmentosa or age-related macular degeneration, intracortical visual and auditory prostheses for blind and deaf patients, peripheral nerve prostheses for the spinal cord injured, and electrodes for stimulation-based therapies such as deep-brain-stimulation (DBS) and cardiac pacing. Neural prostheses are being developed for rehabilitation in spinal cord injury, stroke, and disease-related sensory deficits. Electrical-stimulation based therapies are being developed for the treatment of neuro- degenerative diseases such as essential tremor and Parkinson's, and the treatment of epilepsy, depression and eating disorders. Many of these applications involve a direct interface to the nervous system and require small-area electrodes with recording and stimulation capabilities beyond those available with noble metals. This proposal addresses the development of electro-polymerized films of conductive polymers as electrode coatings for the recording and stimulation needs of electrodes used in these prostheses and therapies. The potential advantages of the conductive polymers over competing electrode coatings are an exceptionally high charge-injection capacity and the possibility of developing coatings that contain biologically active molecules to promote the formation of a stable and functionally enhanced nerve-electrode interface.