近年來對於便宜且快速的診斷方式需求逐漸提升，促使了許多定點照護(Point of Care, POC)裝置（如：血糖機、驗孕棒等）的蓬勃發展。定點照護診斷能免除樣本運送至實驗室之步驟，並且能在數小時甚至數分鐘內得到結果。應用於早期疾病檢測，如若能夠快速得知診斷結果，除了能早期發現早期治療，亦能降低醫療之成本。體外檢測醫療器材為發展中之定點照護裝置重要的一支，透過非侵入式的診斷方式，除了能夠避免感染的風險，亦能提高患者檢驗的意願。隨著生物指標蛋白的發現與發展，透過檢測特定指標性蛋白的濃度，能夠判定受試者之健康狀態，提供醫生判斷之根據。但指標性蛋白之濃度於體液中往往極低而不易偵測，故達到最低之偵測極限即為各研究努力的目標。
有鑑於此，本研究提出一個檯式的光電裝置，並將其運用於糖尿病視網膜病變之檢測。此光電裝置應用之原理為快速動態圖紋法，原為一顯微鏡之系統。透過利用簡易之光學零件重新組裝，本研究提出一個相較便宜之檯式快速圖紋裝置，並提供與原裝置相同甚至更佳之檢測敏感度 (11 ng/ml) 。此平台所搭配的微珠式免疫反應，是透過將特定的抗體修飾於聚苯乙酸微珠上，當檢測指標蛋白 (lipocalin 1)存在於溶液中，會因抗體抗原之特異性鍵結而結合，接著加入修飾有量子點的偵測抗體，會於微珠上形成三明治結構，藉由偵測微珠螢光強度可推知指標蛋白的濃度。於快速動態圖紋平台中，此光電技術能動態收集分散的微珠，此濃縮之能力得以放大微弱的訊號，提高偵測解析度。
於檯式裝置測試實驗中，確認了利用簡易裝置亦能達到濃縮粒子之效果，並能透過動態收集粒子強化訊號。於免疫反應測試實驗中，利用顯微鏡系統確認了實驗方法之可行性，且使用低倍物鏡(10×)取代高倍物鏡(40×)並不會導致偵測敏感度下降。在3微米微珠之免疫反應測試，與模擬結果相比較，確認了改變微珠數量可以動態改變偵測範圍及偵測極限，且0.5微米微珠可透過堆疊成多層結構之效應改善偵測極限。於實際眼淚測試實驗中，此研究提出利用玻璃毛細管非侵入式採集眼淚的方式，並使用3微米微珠於健康人之眼淚測試，結果顯示大部分之眼淚濃度落在減量線之偵測範圍 (110 μg/ml~11 ng/ml) 內且為一個較廣的分布。於眼淚穩定性測試實驗中，使用多管粒子測試相同之眼淚來源，得到樣本濃度為7.85 ±2.97 μg/ml (n=5)，確認了眼淚樣品於此平台的穩定性。目前我們研究的方向著重在糖尿病視網膜病變，此平台之優勢在於僅需改變微珠上修飾的抗體，即能平行移轉至其他疾病之檢測，此外，此檯式裝置使用元件皆非特製零件，故有潛力以較經濟之方式大量複製。

Demand for fast and low cost diagnostic testing tools has increased in recent years, thus prompting the development of point-of-care (POC) devices, such as blood glucose sensors and pregnancy test kits. POC diagnostic testing eliminates certain laboratory testing procedures, thus providing results in hours or even minutes. For diagnosis of an early-stage disease, the fast acquisition of diagnostic results greatly reduces medical cost and facilitates early treatment. In vitro diagnostic device (IVD) is among the popular types of POC devices. In addition to prevention of the risk of infection, testing can also be improved through invasive diagnosis. In view of the breakthroughs and developments in biomarkers, the health condition of a patient can be determined by observing the biomarker concentration. However, the biomarker concentration is extremely low in most cases and is thus difficult to detect. Therefore, researchers have been attempting to obtain the lowest limit of detection.
In this regard, a benchtop optoelectric device was proposed and was used in this study for the diagnosis of diabetic retinopathy. Rapid electrokinetic patterning (REP) is the main principle behind the mechanism of this device, which is originally a microscope system. Through reassembling of the system using simple optical parts, a low-cost benchtop REP system was constructed. It was able to produce equal or even higher resolution (11 ng/ml) than the original setup. In a bead-based immunosensing, modifying specific antibodies on the surface of polystyrene beads with biomarkers (lipocalin 1) induces the specific binding of antibodies to antigens. With the addition of detection antibodies, which conjugate with quantum dots, a sandwiched structure formed on the polystyrene. The mount of lipocalin 1 could be determined by detecting the intensity of fluorescent.In the REP system, dispersed particles can be dynamically collected. With the capability of the REP in concentrating the particles, the signal and the sensitivity can be greatly enhanced.
In the performance test of the benchtop device, the result showed that the particle concentration increased in the device, which is similar to the result of the microscope system, and the signal were enhanced through the dynamic concentration of particles. With regard to the testing of the immunoassay protocol, the protocol was confirmed to be feasible and the sensitivity of the benchtop device was not affected after the replacing 40× objective lens with 10× objective lens. Through comparing with the result in the simulation, the detection range and limit was confirmed to be able to dynamically change by altering the particle number in the experiment using 3 μm particles. The limit of detection can be improved by superpositioning 0.5 μm particles. In the testing of actual tear samples, a non-invasive method to suck the tears using a glass capillary was proposed. The tear samples, ranging from 110 μg/ml to 11 ng/ml, from healthy control were tested. The stability of the tear samples in this platform was examined by using multiple vials in each tear source. The concentration of the tear samples was 7.85±2.97 μg/ml (n=5). Flexibility in detection is the primary advantage of this technique. This platform can be used to diagnose other diseases by altering the antibody on the beads. The benchtop device can be easily reproduced because all its components are not customized.

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