微晶片電泳-化學放光偵測之研究

Abstract

近十年來，電泳及其相關技術於微晶片上的發展已達突飛猛進的境界，然而目前為止，由於玻璃及石英基材擁有為人熟悉的表面、電滲流及光學特性，使得多數晶片製造仍舊以這兩種基材為主，對於分析物的偵測則多半使用雷射激發螢光偵測器，由於製程的繁瑣及造價高昂的偵測系統，使微晶片分析系統價格一直居高不下。 本研究中，選擇塑膠基材製造晶片結合化學放光偵測法以提高微晶片電泳應用性，並具有分析時間短、消耗樣品量少、偵測系統簡單及微小化等優點。研究中以線壓法製程於PMMA基材上壓製流道，壓線條件為102℃加熱8分鐘，貼合條件為104℃加熱8分鐘。此方法製程之晶片具良好流通性，且良率可達70%。經由線壓法製成之晶片，我們選擇luminol-H2O2-HRP放光系統做為化學放光偵測法之測試系統，依序探討電場強度、各反應試劑混合比例、偵測位置等條件，建立最適化學放光偵測系統。為迅速提供足夠的光子產生放光反應，本分析系統選擇luminol 10 mM、HRP 100 units/mL為最適放光條件，於系統最佳條件下，H2O2之線性範圍為0.1 ~ 0.01%，理論偵測極限為0.001%。

Capillary electrophoresis and related techniques on microchips have made great strides in last decade. Typically, these chips were fabricated in glass or quartz because of their well-defined surfaces, good electroosmotic properties, and excellent optical properties for ultra sensitive detection. The analytes were commonly detected by laser-induced fluorescence (LIF). Due to the multi-fabrication process and the expensive detection system, the microelectrophoresis chip system is costly. In this study, we used plastic chips combined chemiluminescence (CL) detection method to explore the application of microchip electrophoresis. The channels were fabricated on poly(methylmethacrylate) (PMMA) by wire imprinting method. The channel was constructed by heating the plastic at 102oC for 8 min. After forming the channel layout, the channel was sealed with another PMMA by heating the plastic at 104oC for 8 min. The luminol-H2O2-HRP system was employed for testing CL system. Several factors such as electric field strength, mixing mold of reagents, and detection point that affected the CL intensity were examined. At the optimized condition, the H2O2 linear range was 0.1% ~ 0.01% with theoretical detection limit at 0.001%.