在檢測溶液生菌領域，對於多數發酵業者來說，目前還是運用傳統的培養塗盤方法，等待24小時的時間後，再依據菌落數量回推原始溶液的生菌數量，但在現今要求快速精準檢測的趨勢下，顯然的此方法確實非常不合時宜，且無法符合目前發酵業者的需求。所以有許多團隊以現今科技，發展出各式各樣的菌量檢測技術，但多數可能有不夠快速或準確、難以商品化，甚或商品化後但價格昂貴等等尚難符合市場需求的問題。本研究承襲研發團隊既有的電動力學操控平台在細菌數快速量化的發展，含核心的環狀指叉型晶片，進行細部檢討並改良一些參數，期望開發出一套足夠精準且符合經濟效益的檢測儀，進而往可商品化的方向邁進。
本研究結合微機電製程技術，以電動力學為基礎下，讓含菌試液經過適當的前處理而達約10 µS/cm下的導電度後，取該160 µl水溶液注入於裝設有環狀指叉型電極 (RIDE)晶片的卡夾中，一旦在其上施加交流電訊號後，即可觀察到細菌等微粒逐漸往電極中心聚集濃縮，全程之顯微影片只需15分鐘的收集觀察，其後續藉由影像擷取和影像分析技術，來辨別溶液中的細菌數。另一方面，受測乳酸菌試液中的含菌數也經由培養法鑑定而於隔日得知數目，且與本研究的RIDE法下所得數目進行回歸比對。結果發現，在500 Hz, 12 Vpp交流條件下取收集8分鐘時的結果，線性度最佳，且也顯示在104到106 CFU/ml之間有較高的再現性，其檢測極限為5×103 CFU/ml。此檢測平台現仍在成大SPARK計畫下培訓，以乳酸菌業應用為初期的利基市場，未來若能配合適當的前處理方法，更將有望於民生用水和飲料，以及醫學臨床檢驗上的後續發展。

關鍵字: 介電泳，交流電滲透流，快速細菌檢測

The current method used by most fermentation-based systems of manufacturing for detecting bacteria in a solution is the traditional plate culture method, which takes at least 24 hours. However, the fierceness of modern competition insists that such processes become ever more rapid and accurate, and the traditional system is becoming outdated. Already, a number of teams have developed a variety of bacterial detection techniques using more advanced technologies, but most of these are problematic, either due to a lack of accuracy or being impractical for commercialization. To overcome these problems, the present study has focused on a rapid detection platform for quantifying the number of bacteria; it is not only accurate but practical, and can be manufactured as a real product to meet modern demand.
In this study, semiconductor technology is used to produce a ring-shaped interdigitated electrode (RIDE) based on electrokinetics. After pretreatment, only 160 μl of the needs to be placed on the RIDE, where, within 15 minutes, 500 Hz and 12 Vpp alternating signal draw biological particles such as bacteria to the center of the electrode after which the total number of bacteria in the solution can be easily identified using image analysis. This ring-shaped interdigitated electrode system had a high linear relationship from 104 to 106 CFU/ml and its detection limit is approximately 5×103 CFU/ml. It is believed that in the future, this can be used for water quality testing, bacteremia and similar processes.
Keywords: Dielectrophoresis, AC electroosmosis, Rapid bacteria detection

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