Multianalyte Nanoprobe for Neurochemicals

描述（由申请人提供）：在单个神经元和神经网络的细胞和细胞外研究中，必须监测电生理和神经化学活动。电化学探针现在已经制造出适合这类研究的尺寸，但是许多神经递质不能用电化学方法检测。此外，化学敏感电极经常消耗它们的目标分析物；在感兴趣的亚微米尺度上，这可能导致正在研究的系统的显著扰动。智能光学系统（IOS）与加州大学洛杉矶分校（UCLA）合作，提出创建一种用于神经化学细胞水平研究的新工具——一种可以测量亚微米体积内多种分析物浓度的探针。在这个提出的传感器中，一个多通道光波导结构，逐渐缩小到比它使用的光波长小的尺寸，将与荧光指示器功能化，与目标物质发生反向反应。这种独特的探针可以在毫秒的时间尺度上连续监测局部神经化学物质的浓度。在拟议项目的第一阶段，IOS将构建3通道和4通道“纳米探针”，并与加州大学洛杉矶分校协商，将使用基于化学和生物化学的识别系统对感兴趣的分析物进行激活。光激活交联将固定嵌入渗透性聚合物“点”中的有机指示剂，直接在光学通道的近场中用于检测离子种类（例如，ca++）和小分子。对于其他感兴趣的物种，光激活结合将用于在光学领域形成一层专利的生化“可逆化学识别单元”。制造后，这些探针将在含有

DESCRIPTION (provided by applicant): In cellular and extracellular studies of individual neurons and neural networks, it is imperative to monitor both electrophysiological and neurochemical activity. Electrochemical probes have now been fabricated at a size scale appropriate for such studies, but many neurotransmitters cannot be detected electrochemically. Furthermore, chemically-sensitive electrodes often consume their target analytes; at the sub-micron size scales of interest, this can lead to significant perturbation of the system being studied. Intelligent Optical Systems (IOS), working with the University of California Los Angeles (UCLA), proposes to create a new tool for cell-level studies of neurochemistry - a probe that can measure the concentrations of multiple analytes in sub- micron volumes. In this proposed sensor a multi-channel optical waveguide structure, tapered to a size smaller than the wavelengths of light it uses, will be functionalized with fluorescent indicators that react reversily with target substances. This unique probe will enable continuous monitoring of localized neurochemical concentrations on a time scale of milliseconds. During Phase I of the proposed project, IOS will construct 3- and 4-channel "nanoprobes" and, consulting with UCLA, will activate them with chemical- and biochemical-based recognition systems for analytes of interest. Optically-activated crosslinking will immobilize organic indicators embedded in permeable polymer "dots" directly in the near field of optical channels for detection of ionic species (e.g., Ca++) and small molecules. For other species of interest, photoactivated binding will be used to form a layer of patented biochemical "reversible chemical recognition units" in the optical field. After fabrication, these probes will be calibrated in stock solutions containing their target molecules, and then used to study extracellular analyte levels in ex vivo (cultured) neurons and brain slices to demonstrate their effectiveness in studying critically important neurobiological phenomena. In Phase II, in vivo applications will be investigated. Ultimately, the IOS-UCLA team plans to combine these optical neuro-nanoprobes with microelectrode-based sensors of similar size to create arrays with large numbers (>100) of multifunction probes for simultaneous electrical and chemical mapping of neurological activity at a scale out of reach, and a level of chemical detail currently out of reach with state-of-the-art technology.