應用氣動式液珠驅動平台於胰島功能篩檢

Assessment of Insulin Release and Screening of Islet of Langerhans on a Droplet-Manipulation Platform

朱旭剛(Hsu-Kang Chu)

指導教授 ： 楊鏡堂

共同指導教授 ： 周涵怡

國立臺灣大學/工學院/機械工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.11025

摘要

本研究主旨為研發胰島的檢測及分離平台，讓胰島的檢測可以在短時間內以目視方式完成，隨後依呈現色度自動篩選分離。首先包覆胰島在液珠中，以滾動的方式在一具有疏水性表面的液珠驅動控制平台移動，接著與檢測試劑的液珠碰撞，完成檢測。平台的製作方式為利用CNC工具機刻製母模，再以PDMS翻模成型一具有氣室排列及氣孔的驅動平台，疏水性表面則使用低功率的二氧化碳雷射蝕刻，蝕刻後的PDMS表面具有超疏水的特性，可以讓液珠在表面呈現懸浮狀態。使用此方法可讓包覆胰島的液珠不需再添加額外能量的方式即可驅動，保有液珠本身的流體性質不受外力所影響而不會傷害到胰島，真空幫浦聯結電磁閥施加負壓的氣動裝置，利用此氣動裝置拉伸疏水性表面下的氣室，改變液珠兩側的表面自由能差異達到操控液珠移動的功能。檢測的方式為讓包覆胰島的液珠與含有葡萄糖的檢測液珠在平台上碰撞，利用葡萄糖刺激胰島釋放胰島素，並使用商用鋅離子檢測試劑(FluoZin-3)量測胰島素釋放時的鋅離子濃度變化，在螢光顯微鏡下可觀察到鋅離子濃度低與高時的螢光強度差異，擷取影像後使用影像軟體Image J計算螢光強度的差值，再配合鋅離子濃度的校正曲線以及ELISA實驗得知胰島的胰島素濃釋放的濃度而判別胰島的好壞。後端的分離同樣使用氣動裝置讓檢測後的胰島在此驅動平台以滾動的方式移動，最後以電磁閥控制氣室的閉合可讓液珠繼續往好胰島區域及不好胰島區域移動，達到分類的目的。期望此胰島的檢測分離系統未來結合前端的自動滴注與後端的控制系統，完成胰島的高通量分離檢測系統，提高糖尿病患者的生活品質。

關鍵字

胰島 ； 胰島素 ； 胰島篩選 ； 疏水性表面 ； 液珠驅動平台

並列摘要

In this study, we developed a droplet manipulation platform for assessment and screening of islet of Langerhans function. The assessment process for islet on this platform takes only a few minutes and needs only two steps. First, a single islet was encased within an aqueous droplet and moved to the superhydrophobic surface on the platform. Second, the droplet that contained test reagent was collided by the droplet that contained islet. By measuring the variation of fluorescent intensity of coalesced droplet, the functional and function-less islets are classified.
The method to fabricate the platform is to use the CNC machine to cut the mold, then pouring PDMS on the mold to make the platform equipped with the array of air chambers. A CO2 laser cutting machine was applied to etch the surface of PDMS. The etched PDMS was superhydrophobic, so droplets can be suspended on the surface. By using pneumatic device to apply minus pressure in the air chamber, a gradient of the Gibbs free energy on the surface caused the droplets are maneuverable on this platform. We utilized glucose to stimulate insulin secretion and a rapid co-secretion of Zinc ion which is detectable by the zinc indicators (FluoZin-3). In order to observe the difference of the intensity between high and low concentration of Zinc ion, we use fluorescence microscope and image software (Image J) to measure the variation of fluorescent intensity inside the droplets. The pneumatic device also used to manipulate the functional/function-less islet passed through different routes. In this study, we classified the functional and function-less islets on a pneumatic maneuverable platform. By combining with automatic drip system and control system in the future, the high throughput islet screening system will be accomplished.

並列關鍵字

Islet of Langerhans ； insulin ； islet screening ； superhydrophobic surface ； pneumatic manipulated platform

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