Collaborative Research: BRAIN EAGER: Stretchable graphene transistors for high signal, high channel count neural recording

该奖项是由生物科学局(BIO)的两个项目--生物研究仪器开发计划(IDBR)和新兴前沿(EF)--联合颁发的。扩大我们对大脑的了解的一个关键障碍是，现有的探索大脑功能的工具根本不能胜任这项任务的艰巨程度。记录神经信号的技术最多允许记录来自数十个或数百个神经元的信号，而此时需要数千甚至数百万个。为了应对这一挑战，需要改进的传感器类型，以更高的信号质量记录神经活动，并且比目前的方法更适合并行记录。这个合作项目将开发一种基于柔性石墨烯晶体管的新型传感器。石墨烯是一种原子组成的薄层碳原子，具有良好的物理、化学和电学性能，可与生物系统连接。然而，将石墨烯晶体管用于单个神经元传感在很大程度上还没有被探索。悬而未决的问题包括神经元和石墨烯之间接触的性质，电信号的最终强度，以及基于石墨烯的电极在大脑中的长期生物兼容性。我们提议的工作将解决这些根本问题。如果成功，该项目最终将带来社会效益，例如更好的神经假体和神经疾病的新治疗方法。研究生将有机会在纳米和神经科学的接口上进行培训，这是美国需要的一个关键领域？S的技术未来。石墨烯可以通过借用日本纸艺Kirigami的技术，被纳米加工成可整合、可伸展的晶体管阵列。该研究小组之前的工作表明，与传统电子设备不同，这种石墨烯晶体管既非常灵活，可以100%拉伸，而不会降低其电气性能。目前的项目将研究Kirigami石墨烯和单个神经元之间的电气和机械相互作用。石墨烯将被切割成不同的图案，以优化石墨烯与单个神经元之间的机械接触。石墨烯在神经元上的包裹将被最大化，石墨烯将被用于测量单个神经元在体外和体内产生的电压尖峰。通过优化石墨烯和神经元之间的共形接触，将有可能测量很大一部分细胞内电位(~70 mV)。石墨烯的半导体特性还将被用于将生物电子信号放大到强健的水平，以促进对数千个神经元信号的多路检测。

This award is jointly made by two programs the Instrument Development for Biological Research program (IDBR) and Emerging Frontiers (EF) in the Directorate of Biological Sciences (BIO).A key roadblock to expanding our knowledge of the brain is that existing tools to probe its function are simply not up to the enormity of the task. Techniques for recording neural signals allow at most signals from tens or hundreds of neurons to be recorded, when thousands or even millions are needed. To address this challenge, improved types of sensors are required that record neural activity with greater signal quality and are more suited to parallel recording than current approaches. This collaborative project will develop a new type of sensor based on flexible graphene transistors. Graphene is an atomically thin sheet of carbon atoms that exhibits desirable physical, chemical, and electrical properties for interfacing with biological systems. However, the use of graphene transistors for single neuron sensing is largely unexplored. Open questions include the nature of the contact between the neuron and the graphene, the ultimate strength of electrical signals, and the long-term biocompatibility of graphene-based electrodes in the brain. Our proposed work will address these fundamental questions. If successful, this project will ultimately lead to societal benefits such as better neural prosthetics and new treatments for neurological disorders. Training opportunities at the interface of nano- and neuroscience, a key area of need for America?s technological future, will be available for graduate students.Graphene can be nanofabricated into arrays of conformable, stretchable transistors using techniques borrowed from the Japanese paper art of kirigami. Prior work of this research team has shown that unlike traditional electronic devices, such graphene transistors are both extremely flexible and can stretch by 100% without degrading their electrical properties. The current project will investigate the electrical and mechanical interactions between kirigami graphene and individual neurons. Graphene will be cut into different patterns to optimize the mechanical contact between graphene and single neurons. Wrapping of graphene on the neuron will be maximized and the graphene will be used to measure voltage spikes produced by individual neurons, both in vitro and in vivo. With optimized conformal contact between graphene and neurons it will be possible to measure a large fraction of the intracellular potential (~ 70 mV). The semiconducting properties of graphene will also be used to amplify the bioelectronic signals to robust levels to facilitate multiplexed detection of thousands of neuron signals.