微電極陣列於心肌細胞動作電位量測研究

Abstract

本篇論文的主要研究目的是在建立一生物電訊號的量測平台，藉以瞭解生物訊息是如何傳遞的。然而記錄生物電生理訊號的方式有很多，在本篇論文中是採用微電極陣列（microelectrode array, MEA）來獲取細胞的電生理訊號。利用微電極陣列量測細胞電生理訊號之前，可透過電阻抗量測來了解微電極之阻抗特性或細胞貼附與否。因為量測到的細胞電生理訊號強度會受到細胞貼附的程度所影響，故對電極表面進行修飾使細胞更容易貼附於電極上是必要的。由於細胞的電生理訊號很小，易被雜訊所覆蓋，因此需要將所得之訊號經過適當的濾波放大處理，使訊號更加清晰。故本篇論文使用鎖相放大器對訊號進行處理，並藉由NI-DAQ將訊號擷取且數位化後儲存至電腦。由於心肌細胞所造成的電生理訊號比神經細胞大，因此在初期建立生物電訊號的量測平台時，以心肌細胞來進行實驗室比較可行的。基於上述的介紹，本篇論文成功利用直徑為20、40、60、80和100 μm的圓形微電極，記錄到心肌細胞的電生理訊號；而當添加腎上腺素（epinephrine）至心肌細胞時，利用此量測系統可觀察到心肌細胞跳動強度與頻率之變化。

The objective in this research is to set up a measurement platform which could record the electric signal called action potential from living cells. Then we can understand the communication of cells. However, there are many kinds of method to record the action potential. In this research, we use the microelectrode array （MEA） to capture the electrophysiological signals. Comparison to the traditional patch-clamp technique, it is non-invasive for cell. On the other hand, the microelectrode array could be used to impedance measurement. By the result of the impedance measurement, we know the characteristics of electrodes and the adhesion of cells. Because the electrophysiological signal is weak, the signal processing is by the lock-in amplifier then acquisition through NI-DAQ. Base on the above strategy, we demonstrate the recording of the electrophysiological signals by circular electrode which diameter is 20, 40, 60, 80, and 100 μm. Otherwise, the increase of contraction rate was measurement by our measurement system after the treatment of epinephrine.