Stimulus-responsive, Mechanically-dynamic Nanocomposite for Cortical Electrodes

用于皮层电极的刺激响应、机械动力学纳米复合材料

• 批准号: 7273887
• 负责人: DUSTIN J. TYLER
• 金额: $ 16.88万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7273887
• 关键词: Behavior; Biological; Brain; Cataloging; Catalogs; Cerebrospinal Fluid; Cerebrum; Characteristics; Chemicals; Chemistry; Chronic; Chronic Phase; Class; Classification; Complex; Condition; Connective and Soft Tissue; Data; Dermis; Development; Device Designs; Devices; Electrodes; Engineering; Environment; Exhibits; Future; Goals; Human; Immersion Investigative Technique; Immunohistochemistry; Implant; Ions; Mechanics; Mediating; Medical Device; Medical Technology; Metals; Methods; Motion; Neurons; Operative Surgical Procedures; Optics; Orthopedics; Performance; Polymers; Positioning Attribute; Preparation; Process; Property; Protocols documentation; Range; Rattus; Research Personnel; Sea Cucumbers; Series; Stimulus; Structure; Techniques; Technology; Temperature; Tensile Strength; Testing; Tissues; Work; base; biomaterial compatibility; brain tissue; concept; implantation; improved; in vivo; innovation; light microscopy; nanocomposite; new technology; novel; programs; prototype; relating to nervous system; research study; response; theories; tool

DESCRIPTION (provided by applicant): Cortical electrodes offer an intimate interface to the complex activity of the brain. They are an enabling technology for advanced brain therapies that will significantly enhance the human condition, as well as, fundamental tools for investigating the operation of the brain. One of the limiting factors of current technology is a mechanical mismatch between the electrode and the cortical tissue. While a stiff electrode is advantageous during implantation and positioning, a chronically stiff electrode causes micro-motion, micro-damage, and chronic astrocytic response in the brain tissue. An ideal electrode would have a high modulus during insertion and a low modulus thereafter. Inspired by the soft connective tissues of echinoderms, we have embarked on the exploration of a highly innovative and novel general class of polymer nanocomposites, which are targeted to dynamically change their mechanical properties in response to a stimulus, such as temperature or pH change, electrical or optical field, or concentration of specific ions. We propose to exploit chemical stimuli (ion concentrations or pH) for the mechanical switching of polymers that form the basis of adaptive cortical electrodes. Initial feasibility of the mechanically dynamic properties of the composites have already been demonstrated. In this proposal we will further study their properties and develop them for use in biomedical applications. The first aim is to optimize the composition for optimal performance in the cortex environment. The optimal material will be stiff in an ambient environment and dynamically change in response to the chemical environment of the cortex to match the cortical tissue mechanics when implanted. We will characterize the mechanical properties and dynamics, as well as, the basic techniques processing the material into devices designed for biological applications. The second aim is to understand the chronic astrocytic and tissue response to the polymer. The overall goal of this project is create and understand a stimulus-responsive, mechanically dynamic nanocomposite available for biomedical and neuroprosthetic applications. The first application studied in this proposal will be as a substrate for cortical electrodes.

描述(由申请人提供)：皮质电极为复杂的大脑活动提供了一个亲密的接口。它们是先进大脑疗法的使能技术，将显著改善人类状况，也是研究大脑运作的基本工具。当前技术的限制因素之一是电极和皮质组织之间的机械不匹配。虽然硬电极在植入和定位过程中是有利的，但长期硬电极会在脑组织中引起微运动、微损伤和慢性星形细胞反应。理想的电极应该在插入过程中具有较高的模数，在插入后具有较低的模数。受棘皮动物柔软结缔组织的启发，我们开始探索一类高度创新和新颖的聚合物纳米复合材料，其目标是响应刺激，如温度或pH变化，电场或光场，或特定离子的浓度，动态改变其力学性能。我们建议利用化学刺激(离子浓度或pH)来进行聚合物的机械切换，这构成了自适应皮质电极的基础。复合材料的力学动态性能的初步可行性已经被证明。在这项提案中，我们将进一步研究它们的性质，并开发它们在生物医学应用中的应用。第一个目标是优化成分，以在皮质环境中获得最佳性能。最佳材料在周围环境中是僵硬的，并随着皮质的化学环境而动态变化，以匹配植入时的皮质组织力学。我们将描述材料的机械性能和动力学，以及将材料加工成用于生物应用的装置的基本技术。第二个目的是了解慢性星形细胞和组织对聚合物的反应。该项目的总体目标是创造和理解一种可用于生物医学和神经假体应用的刺激响应型、机械动态纳米复合材料。这项提议中研究的第一个应用将是作为皮质电极的衬底。