乙型鏈球菌 (GBS) 為一種人體內常在的革蘭氏陽性菌，主在分布在消化道系統和泌尿道系統。根據臨床統計約有20% 的孕婦體內含有此菌，若新生兒感染到此菌容易造成肺炎、腦膜炎甚至敗血症等會造成嚴重後遺症的疾病，因此為孕婦產檢的重要項目之一。目前產檢的SOP是在預產期前三到五週進行檢查，所需約三到五天的檢查時間，但此耗時長的檢測方式無法應對如早產等緊急的突發狀況。針對臨床檢測的缺點，本研究將展示一種以電動力學原理為理論基礎的環狀指叉型電極，並藉此發展一套快速檢測平台。透過電動力學中的介電泳力和電滲流收集如細菌等微米粒子的能力和使用螢光抗體來進行菌種辨識，搭配對螢光收集影像的顆數分析及細菌螢光檢量線，便可避開如塗盤培養法等耗時長的方法，提供另一選擇來達到快速檢測的目地。樣本的前處理分為預培養和菌種螢光標示，預培養為使用10% Lim broth 培養10小時；螢光抗體的混和時間為1小時，而洗淨時離心參數為5000g進行10分鐘。電極的電性操作參數為12 Vpp, 500 Hz，收集時間為8分鐘。平台的細菌濃度檢測極限為臨床檢體中30顆，培養後樣本濃度10^6~10^4 CFU/ml。總檢測時間約為12小時而模擬樣本的檢測準確度為75%。在未來，在搭配不同螢光抗體的使用下，此環狀指叉型電極平台還可應用在其他需要進行細菌檢測的領域，如益生菌等發酵產業以及醫療產業等。

Group B Streptococcus (GBS) is a kind of gram-positive bacterium colonizing around 20% of pregnant women. Since newborns lack mature immune system, they will easily get diseases such as pneumonia, meningitis and even sepsis after getting infection. It takes three to five days for the clinical method to get the result. But this time-consuming method cannot cope with emergency situations such as premature birth. Because of this unmet need, a rapid GBS detection platform based on a ring-shape interdigitated electrode (RIDE) is developed in this study. After the pretreatment protocol, the bacteria in the sample will be concentrated by dielectrophoretic and AC electroosmotic force. The CCD camera and microscope are applied to capture the collection image and detection result can be obtained after combing the image analysis result and a fluorescence calibration curve. The entire detection will be finished within 12 h. For the pretreatment process, the sample will be cultured first in 10% Lim broth for 10 h and then mixed with fluorescent antibody for 1 h. The centrifugal parameter of buffer washing is 5000g for 10 min. The operating parameters for the electrode are 12 Vpp, 500 Hz, and the collection time is 8 min. The detection limit of the platform’s sample bacteria concentration is 〖10^6~10〗^4 CFU/ml. The spiked samples have been detected and the accuracy is 100%. In the future, clinical sample will be tested to verify the feasibility of applying the platform in medical industry. By combining it with the use of different fluorescent antibody, the platform can be applied in fields, which requires bacteria detection such as probiotic fermentation industry.

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