NOVEL BIOSENSORS FOR SPECIFIC NEUROTRANSMITTERS

本提案描述了新的基于酶的设计和测试 神经递质乙酰胆碱、谷氨酸、 和天冬氨酸，在其中黄素氧化还原之间的电子通讯 氧化酶和电极的中心是通过供体网络实现的- 受体继电器与柔性硅氧烷聚合物化学结合。因为 电子转移介体共价连接到不溶于水的 聚合物，不能从电极扩散，这些传感器应该是 适合于植入，因此在体内将有用 神经化学研究。第一阶段的拟议研究计划涉及 通过以下方法开发这些传感器：构建 含有乙酰胆碱酯酶和胆碱的氧化还原聚合物修饰传感器 酶(用于乙酰胆碱检测)、L-谷氨酸氧化酶(用于谷氨酸 检测)和L-天冬氨酸氧化酶(用于天冬氨酸检测)； 聚合物结合电子继电器的数量，优化传感器响应 对于衬底，最小化工作电压(以降低任何 由于易氧化的物种)，并消除任何减少 由于溶解氧而产生的反应。此外，为了增加 对乙酰胆碱的响应，消除虚假阴离子的干扰 种类，并防止传感器结垢，一种商业上可用的阴离子 乙酰胆碱传感器的涂层将使用聚酯磺酸。

This proposal describes the design and testing of new enzyme-based amperometric sensors for the neurotransmitters acetylcholine, glutamate, and aspartate, in which electrical communication between the flavin redox centers of an oxidase and an electrode is achieved via a network of donor- acceptor relays chemically bound to a flexible siloxane polymer. Because the electron transfer mediators are covalently attached to an insoluble polymer and cannot diffuse away from the electrode, these sensors should be suitable for implantation, and thus would be useful for in vivo neurochemical research. The proposed research plan for Phase I concerns the development of these sensors through the following approach: construct redox polymer-modified sensors containing acetylcholinesterase and choline oxidase (for acetylcholine detection), L-glutamate oxidase (for glutamate detection), and L-aspartate oxidase (for aspartate detection); by varying the number of polymer-bound electron relays, optimize the sensor response to substrate, minimize the operating voltage (in order to decrease any interface due to easily oxidizable species), and eliminate any decrease in response due to dissolved oxygen. In addition, in order to increase the response to acetylcholine, eliminate interference due to spurious anionic species, and prevent sensor fouling, a commercially available anionic poly(ester sulfonic acid) will be used to coat the acetylcholine sensor.