精確且快速的檢測出致病菌的種類及藥物感受性對於臨床的診斷與治療是極為重要的。雖然傳統微生物檢測方法可提供精確的結果，然此過程是很耗時的。因此於本研究導入了介電泳分離技術，成功發展出一準確而快速的細菌藥物感受性方法。介電泳是以微粒與溶液間不同的電特性與具有非均勻性的高、低電場作用下產生電極化現象，使微生物往高或低電場強度的移動而分離。
　　本研究中的介電泳晶片電極，採取多項式(polynomial)形狀可為介電泳分離技術提供顯著的正、負介電泳現象。研究結果顯示，介電泳力之大小與方向與微生物與溶液的電特性、外加交流電場強度等參數有關，而且實驗數據也探討出介電泳之電訊號最佳的頻率為0.1~20 MHz，而電壓範圍不宜大於12 Vpp。在此基礎下，我們以介電泳分離技術針對微生物進行了三項應用：(1)不同yeast種類的分離測試結果，發現可在10 mM KCl溶液中，以1 MHz正弦信號，將菌株較大的yeast種類吸附至電極邊緣(正介電泳力)，然菌株較小的yeast種類可被排斥至電極之外區域(負介電泳力)。(2)E. coli受不同濃度之抗生素作用於2小時之後的感受性試驗中，於280 mM mannitol溶液中，以10 MHz頻率，即可將受抗生素抑制的E. coli被介電泳力 斥至電極之外區域，不受抑制的E. coli則吸附至電極邊緣。(3)H. pylori於基因變異後的結構差異表現之檢測研究中，發現BabA與SabA蛋白質表現與否，於DI water溶液中，分別在10 MHz及5 MHz條件下，可予以檢測；而鞭毛之存在與否，於280 mM mannitol溶液中，10 MHz頻率，可予以分離及檢測。
　　藉介電泳分離技術於檢測微生物的研究當中，已成功分離出具型態差異的yeast、受抗生素抑制與否的E. coli以及經基因剔除技術後之蛋白質表現與否的H. pylori。由以上應用例顯示，此技術應可運用於更多微生物的相關檢測上，依試樣細菌組成變化差異的相關測試中，推測將會獲得更多準確與快速之檢測結果。

　　It is important to develope a method for rapid identification a antimicrobial susceptibility test of pathogens isolated from clinical samples. Although conventional methods could provide accurate results, the procedures are relatively time-consuming. In this research, a dielectrophoretic (DEP) technique has been successfully applied for rapid identification and antimicrobial susceptibility testing of pathogens. Dielectrophoresis is the motion imparted on electrically neutral, but polarized, particles subjected to non-uniform electric fields.
　　The DEP chip based on obviously DEP force was produced by the polynomial electrodes. The research showed that DEP force (FDEP) varied with dielectric properties of particles and medium and the applied voltage across the electrodes. Electric signal of frequency range is from 0.1 MHz to 20 MHz and a voltage smaller than 12 Vpp were used in the experiments. The results showed that the different yeasts could be separated based on different cell size. Larger yeasts were attracted to the electrode edge by positive DEP force at 1 MHz in 10 mM KCl medium. On the other hand, in the antimicrobial susceptivity test of E. coli, the inhibited E. coli cells could be separated at 10 MHz in 280 mM mannitol medium due to negative DEP force. Finally, it was shown that H. pylori cells expression BabA and SabA could be separated from those without expression of these two genes at 10 MHz and 5 MHz in DI water. H. pylori having flagella or not also could be separated at 10 MHz in 280 mM mannitol medium.
　　The above results demonstrate a good method for separating microorganisms based on their differences in size and cell structure.

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