ONLINE MEASUREMENT OF BRAIN GLUTAMATE WITH AN ENZYME/POLYMER-COATED TUBULAR ELECTRODE
ONLINE MEASUREMENT OF BRAIN GLUTAMATE WITH AN ENZYME/POLYMER-COATED TUBULAR ELECTRODE
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DOI：
10.1021/ac00085a016
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发表时间：
1994-07-01
影响因子：
7.4
通讯作者：
FILLENZ, M
中科院分区：
文献类型：
--
作者：
BERNERS, MOM;BOUTELLE, MG;FILLENZ, M
描述了一种在线管状电极系统，其提供脑微透析液中谷氨酸的真实的时间测量。其基于酶谷氨酸氧化酶（EC 1.4.3.11）和在铂电极上在600 mV（相对于Ag/AgCl）下检测H2 O2。将酶固定在邻苯二胺层中，该邻苯二胺层在pH 7.0的磷酸盐缓冲液中以750 mV电聚合。该层的厚度为10-15 nm，能够实现良好的酶负载和快速的响应时间。该聚合物的能力，以阻止电活性干扰物，如抗坏血酸和尿酸结合预氧化系统运行在600 mV导致在一个几乎无干扰的谷氨酸测定与0.3 μ M的检测下限的存在下，生理水平的干扰物，4 nA/μ M的灵敏度，和线性区域高达30 μ M。该系统被优化用于植入脑中的微透析探针，并以2 μ L/min灌注。
An on-line tubular electrode system is described which provides real time measurements of glutamate in brain microdialysate. It is based on the enzyme glutamate oxidase (EC 1.4.3.11) and the detection of H2O2 on a platinum electrode at 600 mV vs Ag/AgCI. The enzyme is immobilized in a layer of o-phenylenediamine electropolymerized at 750 mV in a phosphate buffer, pH 7.0. The layer is 10-15 nm thick and enables good enzyme loading and fast response time. The ability of the polymer to block out electroactive interferents like ascorbate and uric acid combined with a preoxidation system run at 600 mV resulted in a virtually interference free glutamate assay with a lower detection limit of 0.3 mu M in the presence of physiological levels of interferents, a sensitivity of 4 nA/mu M, and a linear region up to 30 mu M. The system is optimized for use with a microdialysis probe implanted in the brain and perfused at 2 mu L/min. It provides a time resolution of