本研究之概念設計與實驗執行在於結合奈米粒子及微晶片技術，以建立新型之免疫分析系統。在此研究中，我們利用奈米粒子標記技術並配合銀析出反應，提供另一種有效且方便的免疫分析檢測方式。此外，在微晶片上執行免疫分析程序具有改良多樣性、低樣本用量與高靈敏度等特性，且可以縮短偵測反應的時間。

　　有別於傳統酵素標記的免疫分析(enzyme-linked immunosorbent assay, ELISA)，我們採用現行傳統抗原抗體在晶片表面之固定化技術，並加入銀析出增強溶液，以增強金奈米粒子產生的反應偵測訊號。本研究利用protein A與免疫球蛋白G (IgG) 作為免疫分析模型，以探討新型免疫分析之檢驗可行性與效能。此外，實驗的規劃與架構將朝兩個方向來探討：(一)兩層分析模式，直接檢驗固定在基材上的抗原，並調整實驗偵測的最佳條件；(二)三明治分析模式，利用兩層抗體包夾方式以對抗原作定性與定量之分析。

　　研究結果顯示，本研究策略可以完成免疫分析的步驟與目標，且使用的兩種偵測方式也可配合銀析出現象訊號產生可供檢測之訊號。基於結合微晶片、奈米應用技術、化學反應訊號增強技術，與提供光學與電性偵測成果，本研究建立全新、快速、靈敏之免疫分析系統。相信本研究之高應用性、高生化反應效能及高靈敏度，將對免疫分析系統提供嶄新的思維，和立下新的里程碑。

　The design and experiment of this research lie in combining the microchip and nanoparticles to set up a new silver-precipitation immunoassay system. In this study, gold nanoparticle-labeled antibody is coupled with silver enhancement method to provide an alternative of effective and convenient immunoassay. In addition, the immunoassay carried out on the microchip has the advantages of versatile applications, lower sample consumption, shorter detection time and high sensitivity.

　Compared with traditional enzyme-linked immunosorbent assay (ELISA), we adopt the immobilization of antigen or antibody on the chip surface, and introduce silver enhancement method to magnify the detection signal generated by the gold nanoparticle. Protein A and immunoglobulin G (IgG) are selected as the model immunoassay to estimate the feasibility and efficiency of the silver-precipitation immunoassay. There are two major formats developed in this study: 1. direct immunoassay (two-layer format), the antigen is immobilized on the chip directly to optimize the assay conditions; 2. sandwich immunoassay (sandwich format), primary and secondary antibodies are used to quantify and qualify antigens.

　The results show that the silver-precipitation immunoassay can be measured with optical scanning and electro-signal detection methods. The relationship between concentration and signal is established and the antigen detection limit is 1 ng/mL. The high applicability and biochemical efficiency of this study can provide an alternative for rapid, sensitive and convenient immunoassay.

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