近年來，由於紙基微流體裝置具有生物相容性、價格低廉、可生物降解、並且由毛細力驅動而無需外部幫浦的特點，因此在化學和生物檢測與分析，環境監測，食品安全等方面的應用受到了廣泛關注。現下製備紙基微流體裝置的方法繁多，如：paper cutting, screen printing , photolithography 等多種方法。本研究中，我們將透過噴灑方式製作紙基微流體裝置，首先使用影印紙，藉由列印機列印出流道圖案的紙張，再將其以疏水性材料進行噴灑，利用紙張上的碳粉作為遮罩使得溶液無法滲透，未被碳粉覆蓋處則會被滲透形成疏水區域，噴灑後去除多餘溶液，加熱乾燥並固化高分子後即可得到微流體裝置。實驗結果顯示，碳粉足夠緻密，因此能夠作為遮罩，進而限制疏水材料區域，經噴霧法製造紙基可形成完整的利用噴霧法得到的紙基晶片進行葡萄醣的檢測，與其他方法製備紙基微流體裝置相同，皆可得到一線性關係。

In recent years, paper-based microfluidics has received great attention and been applied in many areas such as chemical and biological detection and analysis, environmental monitoring and food safety inspection. This is because paper-based microfluidics possesses many merits like fluid transport by capillarity without pump, availability, low cost, being biocompatible and biodegradable, pre-loading of reagent, incineration after usage, etc. Numerous methods were proposed and demonstrated to fabricate paper-based microfluidics such as paper cutting, wax printing, screen printing, embossing, photolithography, and so on. In this study, we proposed to fabricate paper-based microfluidics by spraying method. The major highlight is that, instead of using the filter paper, the printing paper which is much easily accessible and substantially low cost was tested. The processing parameters such as toner coverage, hydrophobic material for spray, heating, and so on were investigated. The results showed that the toner coverage was increased after printing, at least, three times. The commercially available wax spray could be used to create hydrophobic barrier to serve as the channel wall, however, the shelf life was only 30 mins. The diluted polydimethylsiloxane solution showed a better result by extending the shelf life to, at least, a month. The plasma treatment of the paper to increase its hydrophilicity might be an option if the paper was not placed in the ambient for certain time prior to usage. The glucose detection was conducted using the device as fabricated and a linear range between 1-10mM was obtained.

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