鮑氏不動桿菌之快速檢測在院內極其重要以預防醫療照護相關感染。尤其針對細菌檢測的早期診斷可以有效增加治療功效。在本研究中，我們提出了一種整合型定點照護設備，可在30分鐘內以雙重適體技術檢測細菌。此設備整合光二極體激發螢光之模組，其接收到的訊號可被光二極體激發，並以光電二極管量化數據，由此可實行一具有高靈敏性及高專一性之細菌量化診斷。整個過程可以在由永久性磁鐵及電磁鐵之組合之電磁控平台上操作。在施10伏特之電壓時，微型幫浦可以達到270 µL/min的傳輸速率，並適合用於定點照護上之應用。本研究使用磁珠系統，表面接上AB菌專一適體來抓取樣品中的細菌，並用第二段適體接上量子點以定量細菌。檢測極限為每反應103顆鮑氏不動桿菌，與本文所提及之一篇文獻比較後有相當的競爭力。此新的生物技術不僅縮小了設備的尺寸，且具有低消耗及低成本的特性。此研究是首次顯示一可以執行雙重適體技術之細菌檢測的全自動化定點照護設備並使用電磁驅動之微型幫浦及微型混合器。在不遠的將來，此設備在臨床上快速診斷AB菌具有不容小覷之潛力。

Rapid detection of Acinetobacter baumannii (AB) is important in hospitals to prevent healthcare-associated-infections. The earlier the diagnosis could be performed, the better the efficacy of treatment that could be achieved. In this study, an integrated microfluidic device for bacterial diagnosis within 30 minutes utilizing a new dual-aptamer assay for point-of-care (POC) applications has been developed. The microfluidic device was further integrated with a light-emitting diode (LED) induced fluorescence module, such that the signals could be induced by a LED and quantified with a photodiode, for the quantitative diagnosis of bacteria with high sensitivity and specificity for POC applications. The entire procedure could be performed on an electromagnetic-driven platform equipped with micropumps, microvalves and micromixers with a combination of permanent magnets and electromagnets. The pumping rate of the micropump was measured to be 270 µL/min with an applied voltage of 10 V, which is amenable for POC applications. Magnetic beads surface-coated with AB-specific aptamers were used to capture bacteria in samples. Then a second aptamer and quantum dots were used to quantify the amount of bacteria. The limit of detection (LOD) for AB diagnosis was experimentally found to be 102 colony-forming unit (CFU)/reaction, which is comparable with the ones reported in literature. Not only could the new method of the biological assay minimize the dimensions of the equipment, but also reduces the power consumption and cost. This is the first time that an automatic POC device was demonstrated which could perform a dual-aptamer assay to diagnose AB by using electromagnetic-driven microfluidic system. It has great potential for fast diagnosis of AB in clinics in the near future.

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