使用聚雙甲基矽氧烷材料製作柱狀複合式透鏡運用於提升微流體系統中的螢光反應

Abstract

微流體系統經常應用於生醫與化學檢測中，並且使用螢光反應來偵測。由於偵測的樣本劑量很少，被激發的螢光是很微弱的。因此，大部份的微流體系統需要許多光學元件，例如濾片、透鏡或微結構去增加螢光偵測效率。然而，使用這些元件的共同問題是複雜的製作過程和昂貴的成本。本研究提出一個微型化、柱狀與複合式的PDMS透鏡，用來同時聚焦激發光源並增加螢光的接收效率。使用複合式透鏡將雷射聚焦透鏡與螢光收集透鏡結合，可以讓單一透鏡具有兩種功能，並減化組裝與架設的過程。此外，使用PDMS材料相較於傳統光學元件有低成本和容易製作的優點。在激發光聚焦的量測中，此複合式透鏡可以將聚焦點大小縮小 81.7% ，並且有 93.39% 效率的提升。在螢光聚焦的量測中，此複合式透鏡對於Rhodamine 6G 和 Nile Red 染劑，分別提升了 85.00% 和 108.42% 的螢光接收效率。

Microfluidic systems have recently been developed and applied for many biological and chemical applications based on fluorescence detections. Because of the tiny amount of sample in the system, the induced fluorescence can be weak. Therefore, most of microfluidic systems require many optical components, such as filters, lens, or micro structure, to enhance the efficiency of fluorescence detection. However, these components encounter the common issues of complex manufacturing processes and expensive costs. In this study, a miniature, cylindrical, and hybrid lens made of polydimethylsiloxane (PDMS) is proposed to focus the excitation light and simultaneously improve the efficiency of collecting fluorescence in the microfluidic device. The hybrid lens integrated a laser focusing lens and a fluorescence collecting lens to achieve the dual functions and simplify the optical setups. Moreover, PDMS has advantages of low-cost and easy fabrication compared with conventional optical components. For the efficiency of focusing excitation light, the proposed hybrid lens can provide an 81.7% reduction of spot size and 93.39% efficiency enhancement of the excitation light. For the integrated efficiency of collecting fluorescence, the proposed hybrid lens can provide 85.00% and 108.42% fluorescence enhancements for Rhodamine 6G and Nile Red respectively.