近來在體外電生理研究中微陣列電極已被應用於表面修改與微壓印圖案規畫的神經網路上進行體外電刺激與記錄其動態響應。因此本研究主要建構神經元培養在多通道電極上之細胞動作電位及電阻抗即時量測，利用電訊號傳遞方式提供神經元細胞達到體外電刺激與紀錄功能，用以觀察神經網路中電生理訊號傳遞情形。在體外電刺激器部分使用具負回授的電路產生穩定雙相微電流脈衝給予神經元細胞電刺激。
經由電阻抗頻譜量測與長時間阻抗監控方法驗證了神經元電極界面是可由電阻與並聯電容所等效，透過此方法提供了神經細胞健康與形態上變化的生理資訊，在長期阻抗內測量中我們使用高滲透壓的PBS液體來模擬體外培養的神經細胞受到刺激或神經形態改變的狀況。在細胞體外電刺激研究中適當的刺激閥值已被找出並由分化的PC12 細胞上記錄到刺激後的電流電生理訊號，在電刺激的結果與神經細胞貼附電極的完整性有相關。在未來發展中此電生理系統將經由微壓印圖案規畫使腦皮質細胞培養在探針式的微陣列電極上進而植入大腦中，希望可以進一步的觀察當神經性疾病時之腦部活動情形。

Recent electrophysiology development of multielectrode array (MEA) allows researchers to perform extracellular stimulation and sensing of patterned neural network cultured on a surface-modified substrate. The aims of this study were to construct an action potential (AP) and impedance measurement system for neurons cultured on multielectrode array (MEA) to validate the extracellular stimulation and recording for observing the electrophysiological signal transmission in neuronal network. An extracellular stimulator with negative feedback to produce the biphasic micro-current pulse for neuron stimulation was built in this study.
In verifying of the sealing resistance and shunt capacitance between the neurons and electrode, experiments were performed by impedance spectra and long-term impedance monitoring for neurons or cells seeded and grew on multielectrode. In the long-term impedance measurement, we used the high osmosis PBS to simulate damage in neurons in vitro. For extracellular stimulation study, neuronal activity of differenced PC12 cells successful was recorded and the suitable stimulation window was determined. However, the stimulation results were affected by electrode impedance as well as sealing impedacen resulting from neuron cells covering the microelectrode. Further development of microcontact printing for patterned neuron network cultured on the MEA should provide an novel platform for in-vitro neuronal outgrowth under varied conditions via impedance and electrophysiological measurements.

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