Enzyme modified amperometric sensors for choline and acetylcholine with tetrathiafulvalene tetracyanoquinodimethane as the electron-transfer mediator
Enzyme modified amperometric sensors for choline and acetylcholine with tetrathiafulvalene tetracyanoquinodimethane as the electron-transfer mediator
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DOI：
10.1016/s0003-2670(96)00492-8
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发表时间：
1997-03
影响因子：
6.2
通讯作者：
Q. Xin;R. Wightman
中科院分区：
文献类型：
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作者：
Q. Xin;R. Wightman
为了更好地了解乙酰胆碱，一种重要的神经递质，及其前体胆碱，乙酰胆碱和胆碱电流传感器已被制作。传感器的性能得到了改善，使胆碱和乙酰胆碱的测量具有高的灵敏度和选择性。该传感器由半径为16.5 μm的斜切和凹陷的碳纤维微电极构成。一种有机导电盐，四硫富瓦烯四氰基醌二甲烷（TTF TCNQ），被用作电子转移介体。微电极尖端的凹槽部分填充有TTF-TCNQ，并覆盖有交联的胆碱氧化酶和乙酰胆碱酯酶。还涂覆了一层薄的Nafion聚合物以增加电极的机械稳定性。所得的乙酰胆碱和胆碱传感器的响应时间为8.2 s，线性范围分别高达50和100 μM。干扰电活性化合物抗坏血酸，尿酸，多巴胺，5-羟色胺（5-HT），和DOPAC在其最大生理浓度低。在大鼠脑切片中获得的数据表明，这些传感器是一个有用的和实用的手段，监测胆碱浓度的变化，在大鼠脑微环境。
To understand more about acetylcholine, an important neurotransmitter, and its precursor choline, acetylcholine and choline amperometric sensors have been fabricated. The performance of the sensors has been improved so that measurements of choline and acetylcholine have a high sensitivity and selectivity. The sensor is constructed from a bevelled and recessed carbon-fiber microelectrode with a radius of 16.5 μm. An organic conducting salt, tetrathiafulvalene tetracyanoquinodimethane (TTFTCNQ), is employed as an electron-transfer mediator. A recess at the tip of the microelectrode was partially filled with TTFTCNQ and covered with cross-linked choline oxidase and acetylcholine esterase. A thin Nafion polymer was also coated to increase the electrodes' mechanical stability. The resulting acetylcholine and choline sensors have a response time of 8.2 s and a linear range up to 50 and 100 μM respectively. Interference from the electroactive compounds ascorbic acid, uric acid, dopamine, 5-hydroxytryptamine (5-HT), and DOPAC was low at their maximal physiological concentrations. Data obtained in slices of rat brain indicate that these sensors are a useful and practical means of monitoring choline concentration changes in the rat brain microenvironment.