近年來許多研究利用光訊號或阻抗量測技術，觀測細胞在不同狀態下的生物活性變化。研究顯示組織內吸收或散射光特性的變化，將會影響生物體內自發性光訊號的改變。另一方面，細胞電阻抗量測值則是取決於細胞與量測介面的貼附能力。因此本研究的目的即是利用微陣列電極技術，同時量測細胞在缺氧缺糖狀況下的光訊號以及電訊號的反應。在本研究中，我們利用光循環器以及自製光纖探針將近紅外光訊號傳導到細胞上，並且經由相同的光纖擷取反射光訊號，同時藉由光頻率調變技術比較原訊號與反射光訊號，以得出振幅與相位的變化。藉著比較細胞光散射訊號與阻抗量測儀量取的電阻抗值，我們可以推測細胞在大腦中風情況下的生物特性。首先我們觀測細胞在不同滲透壓環境下的變化，以驗證系統的可行性。結果顯示不同滲透壓導致細胞體積改變時，細胞光散射訊號的振幅向位也會跟著改變。確定系統可行性與穩定性後，我們量測細胞光電訊號在缺氧缺糖狀況下的反應，並觀察到當細胞受到缺氧缺糖的刺激後有明顯膨脹的現象，同時也伴隨著光訊號振幅上升以及細胞電阻抗下降。當細胞加入神經生長因子後，延遲了細胞膨脹的反應時間，且在光散射與電阻抗訊號上也有相同的延遲現象。由研究結果顯示經由本光電系統架設所得出的光電訊號，不僅能獲得普通細胞型態上的改變，更能得到因細胞內生理狀態變化所導致的不同光電訊號特性。

A number of studies have been conducted using intrinsic optical signal (IOS) or impedance measurement for observing culture cell activity under varied physical or chemical challenges. Research has shown that IOS reflects changes in transmittance and scattering light of tissue. Hence, the impedance is related to the adhesion of cell to the substrate. The aim of this study is to simultaneously record the backscattering IOS and the impedance of cells cultured on multielectrode arrays (MEA) under hypoxic condition using oxygen glucose deprivation (OGD) model. An optical circulator (OC) was adopted as optical probe to deliver the near infrared (NIR) light source and receive backscattering light at the same path aiming the target cells at a close proximity. The optimal probe to dish distance was determined from a series of experiments and theoretical calculation. Frequency-modulated NIR was applied to derive the amplitude attenuation and phase shift between incident and receiving light. The impedance of cells cultured on MEA was scanned using a commercially available LCR meter. During validation experiment of osmotic shock, the changes in magnitude and phase of backscattering light correlated well with osmotic challenges which are mainly attributed to cell volume change. Under OGD test, the intensity of IOS suddenly increased and impedance decreased due to cell swelling. After cell treated with nerve growth factor (NGF), the effect of cell swelling was delayed under OGD which correlated well among IOS, impedance measurements and cell images. In conclusion, both IOS and impedance characterization of neuron cells under OGD condition have been demonstrated in this study. Our simple optical setup could provide additional phase shift information originating from changes in intrinsic optical properties of intracellular fluids and various subcellular components which is beyond only the cellular morphological changes.

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