Functionalized Coatings for Enhanced Neural Interfaces

描述(由申请人提供)：建议开发一种用于记录和刺激神经系统的电极的生物活性涂层。该涂层是基于聚乙二醇/聚乳酸的共聚物(聚乙二醇-聚乳酸)，其中含有一种神经营养因子作为一种缓慢释放的成分。神经营养因子的释放促进了神经突起向电极表面的延伸。电极靠近可存活的神经过程将提高神经记录的稳定性和灵敏度，并可能降低神经兴奋的电荷注入阈值。使用细胞粘附肽对电极进行表面处理也将作为一种在神经营养因子耗尽后保存界面的方法进行评估。我们第二阶段工作的目标是：1)评估神经营养素洗脱聚合物植入微电极上的益处，该动物模型适合皮质内记录，用于对脊髓损伤的体外设备进行直接基于思维的控制；2)评估神经退行性疾病模型刺激电极上神经营养素洗脱涂层的益处，特别是视网膜色素变性视觉假体中的视网膜刺激电极；3)评估黏附分子表面结合涂层用于长期稳定短期神经营养洗脱建立的电极表面神经突起的紧密联系的好处。目前正在为脊髓损伤、耳聋、失明和影响运动的疾病患者开发假体。这些假体将通过电刺激神经或记录大脑中的神经活动来发挥作用。建议在这些电极上使用可生物降解的涂层来增强植入的金属电极与大脑中神经细胞之间的电连接。涂层将洗脱促进神经细胞生长到植入电极上的生物活性分子，提高假体刺激和记录性能的效率和可靠性。

DESCRIPTION (provided by applicant): The development of a biologically active coating for electrodes used in recording and stimulation of the nervous system is proposed. The coating is based on a co-polymer of poly(ethylene glycol)/polylactic acid (PEG-PLA) that contains a neurotrophic factor as a slowly releasable constituent. Release of the neurotrophin promotes the extension of neural processes to the electrode surface. The close proximity of the electrode to viable neural processes will enhance the stability and sensitivity of neural recordings and may reduce charge- injection thresholds for neural excitation. Surface treatment of electrodes with cell adhesion peptides will also be evaluated as a means of preserving the interface once the neurotrophic factor is exhausted. Our objectives for the Phase II effort are 1) to assess the benefits of neurotrophin-eluting polymers on microelectrodes implanted in an animal model appropriate to intracortical recording for direct thought-based control of extracorporal devices for the spinal cord injured, 2) to assess the benefit of neurotrophin-eluting coatings on stimulation electrodes in a model of neurodegenerative disease, specifically retinal stimulation electrodes in visual prostheses for retinitis pigmentosa, and 3) to evaluate the use of surface-bound coatings of peptide adhesion molecules to chronically stabilize the close proximity of neural processes at the electrode surface established by short-term neurotrophin elution. Prostheses are being developed for individuals with spinal cord injury, deafness, blindness and diseases that impair movement. These prostheses will function by electrically stimulating nerves or by recording nerve activity in the brain. The use of biodegradable coatings on these electrodes to enhance the electrical connection between the implanted metal electrodes and nerve cells in the brain is proposed. The coatings will elute biologically active molecules that encourage nerve cells to grow to the implanted electrodes, increasing the efficiency and reliability of the stimulation and recording properties of the prostheses.