面對現今醫病比例不均及偏遠醫療資源不足的情況下，定點照護即時檢測 (Point-of-Care Test)是一種新趨勢，其具有快捷且操作簡單之優點，大大降低醫療人力需求、也可避免醫護人員直接接觸血液，且在短時間內讓醫師能作最有效率的臨床判斷。然而，POCT中的相關研究中，血液前處理為大部分，若欲提高檢測準確度，將血液有效分離是很重要的一環。故本研究整合交叉流與生醫阻抗技術之細胞分離轉盤平台設計，有別於以往的生物轉盤利用離心力與旋轉角加速度所提供之分力(尤拉力)作為工作原理，此設計將利用旋轉提供動力讓目標溶液能夠在交叉流道中被分離，換言之即為在旋轉碟盤上實踐尺寸篩檢之效果，利用此法可增加被檢測之液體量。本實驗透過改變轉速影響分子分離效果，並結合生醫阻抗技術進行分離效果的量測以減少系統的複雜度。從實驗結果得知，實驗時間僅需3秒鐘，當轉速達至3500 rpm，分離效果可以高達96%。雖然本研究設計具有快速分離之效果，但仍然有很多因素需考量。目前實驗僅以假體進行討論，尚未測試實際細胞在此設計之分離效果，但本研究提出整合交叉流與生醫阻抗技術之細胞分離轉盤平台設計，能作為POCT之血液分離診斷應用之設計參考。

Blood is one of the most important material that can be used to diagnose disease. To prevent from the effects of blood cells for cell free plasma detection, the blood separation efficiency is a critical step. In this study, we present a novel continuous flow separator using a cross-flow filter structure on rotating disc. We combined impedance bioanalysis and a simple blood sample separation mechanism into the centrifugal platform, and thus reduces the system’s complexity. The working principle of the proposed separator is based on size exclusion of cell through tangential flow that induced by rotation which is different from the past rotation disc system. As a pilot study of this new centrifugal flow control element, we demonstrate the efficient separation that can collect the amount of the fluid without the molecules from the sample. While the rotation stopped, the result showed that the separation efficiency was only 96% under 3500 rpm within a short, 3 seconds interval, however, we just can find rare particles in the analyst chamber, thus we assumed that the lower efficiency may cause by the amount of fluid. Though the prototype of the design had performance rapid separation, the device still need to improve. Therefore, we conclude that the proposed device can take as reference for the application of blood separation and use for point-of-care (POC) diagnostic system.

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