Implantable Microarray Probe for Real-Time Glutamate and GABA Detection

项目摘要 这项STTR计划将专注于开发和测试一种新型的、市场上第一个植入式生物传感器 在活体内，实时检测伽马氨基丁酸(GABA)和谷氨酸(GLU)，用于动物研究。γ-氨基丁酸 和GLU是神经递质(NT)，对信息处理和可塑性、记忆和 其他功能。谷氨酸是主要的兴奋性NT，GABA是主要的抑制性NT； 它们对正常的大脑功能至关重要。Glu-GABA失调在几种大脑疾病中起着关键作用， 包括癫痫(一种影响1.2%美国人的疾病)、痴呆症(到2050年将影响全球1.3亿人) 还有帕金森氏症(目前影响着150万美国人)。对NT动态平衡的基本认识 包括它的时间成分和它在大脑区域内和跨区域的行为事件中的作用将导致 更好地了解人脑功能和新的更有效的治疗方法。现有NT感测 这些方法一次只能测量一个NT，时空分辨率较差，无法测量NT 电路级的动态，实时连续。我们的目标是开发一种超小巧、灵活(50微米) 亚秒级慢性、直接和同时检测GLU和GABA的神经探头 时间分辨率高，不需要外用试剂。第一阶段专注于制造原型硅 穿透式杆式探头，带4个微图案化传感器和1个微流控按需原位校准器 (ODIC)，优化酶功能化过程，并对测量进行可行性研究 对自由活动大鼠GLU和GABA水平的实时生理相关变化 几周。第二阶段的目标是将探测器升级为抗大脑微运动的杂交硅- 更高功能的柔性聚合物探头(Octrode+2 ODIC微通道)，改进了选择性 在颞叶癫痫大鼠模型中对这些探针进行功能化和验证。多功能ODIC 将用于对慢性测量进行现场校准，并调查3 通过化学调制，胡须桶皮质中相邻的皮质层。完成后，我们预计将 提供市场上独一无二的双NT探头，具有卓越的可靠性和卓越的灵敏度、选择性和 稳定性，所有性能参数都等于或好于当前技术提供的参数。至 实现这一目标，Alcorix将与路易斯安那理工大学的安培NT传感研究专家合作。 来自NeuroNexus的制造先进神经探针的专家，他们将协助混合硅-柔性 聚合物集成、体外和体内评估，以及最终进入市场。拟议的研究还将 支持其他用途，如神经毒素或疾病生物标志物的使用点传感器，以及神经信号 结合特定的局部注射药物进行记录或神经刺激。2023年全球汽车市场 电生理神经探头(Grand View Research)的价格约为2.66亿美元，年复合增长率为3.1%。如果只有1% 这项技术可以占领市场，这将是提议的工作的充分理由。

Project Summary This STTR proposal will focus on developing and testing a novel, first-on-the-market implantable biosensor for in vivo, real-time sensing of gamma-aminobutyric acid (GABA) and glutamate (GLU) for animal studies. GABA and GLU are neurotransmitters (NTs) that are essential for information processing and plasticity, memory, and other functions. GLU is the major excitatory NT and GABA is the major inhibitory NT; a proper balance between them is vital for normal brain function. GLU-GABA dysregulation plays a critical role in several brain disorders, including epilepsy (a disease affecting 1.2% of Americans), dementia (which will affect 130M worldwide by 2050) and Parkinson’s (which affects 1.5M Americans today). A fundamental understanding of NT homeostasis including its temporal components and its role on behavioral events within and across brain areas would lead to a better understanding of human brain function and to new and more effective treatments. Existing NT sensing methods measure only one NT at a time, suffer from poor spatiotemporal resolution, are unable to measure NT dynamics at the circuit level, continuously in real time. Our goal is to develop an ultra-small, flexible (50µm) neural probe for chronic, direct and simultaneous amperometric detection of GLU&GABA, with sub-second temporal resolution and with no externally applied reagents. Phase I focused on manufacturing a prototype Si penetrating shank-type probe with 4 micropatterned sensors and one microfluidic on-demand in-situ calibrator (ODIC), optimizing the enzyme functionalization process, and performing a feasibility study on the measurement of physiologically-relevant changes in the levels of GLU&GABA in real time for freely moving rats for up to 2 weeks. The objectives of Phase II are an upgrade of the probe into a brain micromotion-resistant hybrid Si- flexible polymer probe of higher functionality (octrode + 2 ODIC micro-channels), improvements in selective functionalization, and validation of the probes in a rat model of temporal lobe epilepsy. The multifunctional ODICs will be applied to perform in-situ calibrations for chronic measurements and to investigate the circuit activity of 3 adjacent cortical layers in the whisker barrel cortex via chemical modulation. Upon completion, we expect to deliver a unique-on-the-market dual NT probe of excellent reliability and superior sensitivity, selectivity, and stability, with all performance parameters equal to or better than those offered by current technologies. To achieve this, Alcorix will partner with experts in amperometric NT sensing research from Louisiana Tech U. and experts in the manufacture of advanced neuroprobes from NeuroNexus, who will assist with hybrid Si-flexible polymer integration, in vitro and in vivo evaluation, and eventual market entry. The proposed research will also enable alternative uses such as point-of-use sensors for neurotoxins or disease bio-markers, and neural signal recording or neurostimulation in conjunction with specific locally-injected drugs. The 2023 world market for electrophysiological neuro-probes (Grand View Research) is about $266M, CAGR of 3.1%. If only 1% of that market can be captured by this technology it would be more than sufficient justification for the proposed work.