微電極陣列提供一種電生理方法來紀錄細胞電特性。藉由微電極陣列一方面可用來測量神經細胞與電極介面電阻抗特性，另一方面更可利用多點膜外電刺激方式來了解細胞電生理特性。此研究的目的為建造一套電阻抗和動作電位量測系統用來觀察在缺氧缺葡萄糖環境中體外神經培養網路的電生理訊號傳遞特性。此研究中使用一個可以用來膜外神經元電刺激的雙相微安培定電流刺激器。利用電阻抗監測體外細胞培養時，可以看出細胞貼附、細胞成長與電阻抗存在有清楚的相關性。在只有黃金情況下之電極阻抗呈現穩定的150kΩ，經過PC12細胞貼附於電極之後，其阻抗值快速上升到了286kΩ。且在四天的培養週期穩定的上升到503kΩ。同樣的情形也可在大腦皮質神經元中觀察得之。經由電阻抗在缺氧缺葡萄糖環境中時程之變化，可知其對於細胞具有有效的傷害性。PC12以及大腦皮質神經元細胞經過五天培養後，量測其阻抗值分別為465 kΩ以及516.2 kΩ。在其經過模擬之缺氧缺糖環境刺激下，經過15分鐘後阻抗值幾乎掉到與純黃金之電極阻抗值附近的數值。在膜外電刺激方面，神經元細胞的自主性活動電訊號已經成功的紀錄。請利用對大腦皮質神經元給予適當的刺激參數，可得到其大腦皮質神經元活動。然而，膜外電刺激效果受到細胞貼附電極程度所影響。故利用電極表面處理來讓細胞更容易貼附電極是必需的。藉由此有力的工具可以用來了解各種藥物測試對於神經元網路所造成之電生理特性影響。

Substrate with integrated microelectrode arrays (MEAs) provides an alternative electrophysiological method for recording the electrical activity from excitable cells. With MEAs, one can measure the electrical impedance of neuron electrode interface and elicit electrical stimulation from multiple sites of MEAs to determine the electrophysiological conditions of cells. The aims of this research were to construct an impedance and action potential measurement system for cultured neurons on MEAs to observe the electrophysiological signal transmission in neuronal network during glucose and oxygen deprivation (OGD) condition. An extracellular constant current stimulator producing the biphasic current pulse for neuron stimulation was first built in this study. The impedance monitoring during in vitro cell culture showed that a clear relationship to cell adhesion, cell growth and electrode impedance. The impedance of bared gold was measured at a stable value about 151 kΩ. After the PC12 cells were seeded on the substrate, the impedance dramatically elevated to the 286 kΩ and gradually increased to 503 kΩ during 4 days of culture resulting from the cell growth on the electrodes. Similar properties can be observed on the time-course growth of cortical neurons. After seeding of cortical neurons on the substrate, the impedance was dramatically increased to the 265 kΩ. Then, the impedance of cortical neurons was increased day by day due to the cell growth on the electrodes. From the time-course recording of impedance, OGD condition effectively induced neuronal damage in vitro. The impedance of PC12 and cortical neurons was monitoring during 5 days of in vitro culture was 465.0 kΩ and 516.2 kΩ, respectively. The impedance of both PC12 and cortical neuron decreased rapidly during OGD condition and fell into the level close to that bare gold electrode around 15 min. For extracellular stimulation study, the spontaneous activity was successful recorded in the cultured neurons. The cortical neuronal activity was recorded and the suitable stimulation window was determined. However, the stimulation results were affected by electrode impedance as well as by the sealing impedance resulting from neuron cells covering the electrode. Further development is to utilize surface modification on the electrode for better adhesion of cultured neuron to the electrodes. By using the powerful tools, it can be used as drug screening purpose to monitoring the electrophysiological properties of cultured neuronal networks.

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