DNA 微陣列晶片由於可以大量分析每個基因受調控後，其表現量的變化，對於現今的生物學研究而言，是一種很重要的工具。經實驗後所觀察到的基因表現量的比值所提供的訊息，對於探討基因功能、臨床應用或醫學研究而言無疑是一大幫助。然而，在整個實驗中仍有幾個因素可能會影響到最後結果是我們必須要考慮的，這包括光電倍增管的特性、不同螢光染劑的量子產率不同、所點印上的點體積不同…等。另外，cDNA微陣列的影像亦提供了不少資訊，例如點的螢光強度、點的均勻度以及訊號點與背景值強度…等。
對於我們自行架設的掃描系統而言，經過系統測試及改良後，目前其偵測極限已至3.83 fluorescence molecule/μm2。在微陣列的實驗中，已經可以量測到生物實驗後螢光強度的變化，並與商用掃描器的偵測極限接近。本文將從掃描器的原理、組裝、系統測試、改進過程與結果做一系列的探討。

DNA microarray technology has become an important tool for large-scale gene expression screening and analysis in genomic research. Gene expression ratios derived from spotted-glass micorarray experiments enable researchers to evaluate the molecular underpinnings of cell behaviors and states. However, several factors that affect microarray data have to be noted, including the characters of photo multiplier tube, the quantum yield of Cy3 and Cy5, and the difference of spotted volume etc. The microarray images provide information from spots intensity and characteristics of signal-background segmentation. In this study, we used a homemade scanner system modified by ourself to detect the fluorescence intensity. After some modification and test, the detection limit of our scanner system was about 3.83 fluorescence molecule/μm2, and it sufficed the microarray experiments.
This report will focus on the arrangement and characteristics of scanner. In addition, we discuss future applications and improvement of our scanner system.

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