生物學上所謂的受傷(wound)，是指正常的組織結構或功能受到破壞；而癒合(healing)則是指重建完整解剖構造及功能所經過的一連串複雜動態過程，此過程中有許多因子可促進或抑制此過程，如：維他命C即是促進的因子。實際上，不論組織或細胞，每時每刻都面臨著外來的刺激或傷害；尤以細胞層級的傷害，更是在組織發生變化前就開始發生。故若能對細胞的傷害與癒合進行即時的分析，則對瞭解受傷機轉和研發藥物都有相當的幫助。Scracth wound assay和MTT assay是生物學上常被用來研究細胞層傷害癒合的標準方法，但卻各有很難量化傷口癒合的動態過程，與僅能做各個特定時間點的檢測之缺點。另一個可供選擇則是阻抗量測(EIS)法，其優點為可即時監測細胞變化、易於進行量化分析，亦可依據實驗需求設計不同的電極進行檢測。本研究是將纖維母細胞(L929)培養在以微機電技術製作出的微小城垛型指插電極(IMP)上，利用EIS記錄細胞貼附、受到電傷害的變化和癒合過程，以及維他命C對此過程的影響；同時進行連續攝影，並與MTT assay比較分析。細胞在受到直流電傷害後，在正極上的細胞會因細胞膜穿孔導致細胞產生先腫脹後死亡的變化，然後由旁邊的細胞進行傷口修復。研究結果顯示，此變化在EIS上可即時且連續監測，且其修復趨勢與MTT assay相同。此外，在阻抗量測上，可發現細胞電傷後立即給予100 M維他命C可加速細胞的修復；雖在電傷前給予維他命C無法減少細胞受損，卻同樣可加速細胞的修復。由此可知，EIS是即時且連續監測貼附型細胞變化的有效方法；而IMP則是能量測阻抗變化，亦能造成細胞傷害或死亡的微小電極。此微小電極配合阻抗量測系統不僅可即時研究電傷害對細胞的影響和藥物對電傷修復過程的影響，且可迅速且即時分析細胞產生變化的時間點；並在變化的時間點上，再輔以生化技術進行進一步的分析。對研究傷害癒合和研發藥物而言，是相當有利的工具。

The healing of tissue wound is a cascade of complex, dynamic and multi-cellular process. Many factors control and coordinate this process, including vitamin C. Vitamin C, L-ascorbic acid, is an essential nutrient for humans, an effective antioxidant, an enzyme cofactor for the biosynthesis of collagen, and an electron donor for many enzymes. The dynamic change after cell injury by electric forces, cellular healing process of electric injury, and the role of vitamin C in the healing process are still not clear. Biologically scratch wound assay and MTT assay are the standard methods to evaluate the cellular healing, but both of them can’t detect the dynamic change of healing process. Electrical impedance sensing system (EIS) is an alternative to detect cellular healing process in real-time. In this thesis, we used EIS to monitor the healing process of L929 fibroblasts injured by 30 A direct current (DC) and the effect of 100 M vitamin C added before and after electric injury on interdigitated microelectrode plates (IMP). We found that the size of damaged cells increased first then these cells died and disappeared from IMP gradually and healing process started at the same time. This was compatible with the result of MTT assay. Treated cells with vitamin C after electric injury decreased damage. Besides, the damage in the group of adding vitamin C before electric injury didn’t decrease, but the healing rate is improved.

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