3D列印微流體之開發:以定點照護多重疾病檢測及電化學線上藥物滲透性測試為例

Abstract

隨著3D列印技術解析度的顯著提升，其已成為微流體裝置製作的新興主流，相較於傳統軟微影製程需要靠多層光罩設計堆疊成3D結構，3D列印不僅免除黃光室設備需求，更能夠實現全3D設計與製作，不僅對於儀器環境設備的需求大幅減少，更可以提升設計自由度。因此本論文聚焦3D列印技術在微流體領域的應用。本論文將分為兩部分，第一部分為利用3D列印模具製作之可用簡易工具操作之定點照護多重疾病核酸檢測裝置。該研究利用3D列印製作模具以PDMS翻模成型，透過疏水閥門設計與安排，該流道能夠承受最高25 μL/s之高流速，藉此能夠實現以簡易移液工具進行等量、依序的液體加載。最後結合冷凍乾燥技術與反轉錄恆溫環形核酸增幅法，完成可用肉眼判讀結果之多種病原體的即時核酸檢測平台。 第二部分提出蠟封法整合網版印刷電極於3D列印微流體裝置之技術。該方法透過熔融蠟與材料間的毛細力自動地填入網版印刷電極與微流體間的間隙，且能夠利用毛細閥現象防止蠟溢流，整個蠟封法僅需要將定量的蠟塊融化，接著固化後便能夠固定兩者相對位置，整合過程可以在5分鐘內完成，以達成異質材料的高效整合。透過蠟封法所組成的電化學電極整合微流體裝置，能夠用於開發線上即時監測裝置，該裝置能夠連續記錄分析物濃度隨時間變化曲線。赤血鹽溶液測試下在該為流道裝置中之檢測極限為1.06 μg/mL相比於再開放環境中進行電化學檢測，期檢測極限略微提升，而在進行利用赤血鹽溶液進行透析實驗的研究中，該裝置所檢測到的濃度變化符合理論模型，且最終該系統所檢測到之滲透率達95 %以上，已經符合標準滲透測試儀器之標準，在雙氯酚雙鈉透皮藥物測試中，該系統也能描繪出藥物釋放情形，其藥品滲透率約為80% ± 10%，符合一般凝膠類藥物滲透情形，表明該系統具有用於藥物傳輸監測與新藥開發的應用潛力。

With the advancement in resolution of 3D printing technology, it has become a popular fabrication method for microfluidic devices. Compared with traditional soft lithography that requires multiple layers to create a 3D structure, 3D printing not only eliminates the requirement for cleanroom facilities but also can directly print either the mold with 3D structure microfluidic channel or directly print the 3D resin microfluidic channel; this enhances design flexibility. Thereby, this thesis investigates the application of 3D printed microfluidics. This thesis has two parts. The first part shows a pipette-operable microfluidic device with hydrophobic valves in sequential dispensing. By the design and the arrangement of the hydrophobic valves, the maximum flow rate can reach 25 μL/s, such a high flow rate make the device is capable with hand tools. Furthermore, the device combines freeze-drying technology and reverse transcription loop-mediated isothermal amplification (RT-LAMP) to achieve naked-eye visible multiplex disease point-of-care testing. The second part shows a wax-sealing method for integrating screen-printed electrodes (SPEs) into 3D-printed microfluidic devices. The method used the capillary force of molten wax to autonomously fill the gap between the SPE and the microfluidic device and prevent wax from overflowing into the liquid channels. Upon solidification, the wax securely fixes the relative position of the electrode and the device. The entire wax-sealing process takes only 5 minutes and allows multiple devices to be integrated at the same time. This shows that the wax-sealing method is a highly efficient integration method for a homogeneous-material device. In the potassium ferrocyanide testing, the limit of detection (LOD) is 1.06 μg/mL compared to the open environment LOD of 1.92 µg/mL; shows the device can slightly improve the LOD. In the permeation assay, the release profile follows the theoretical mass transport model. Furthermore, the permeation rate is higher than 95 % which match the requirement of the tools for permeation assay. Furthermore, the device is tested by a commercial diclofenac sodium gel; it is also shows the clear release profile and the permeation rate is 80% ± 10% which is match the common permeation rate of the gel form drug. In conclude, the wax-sealed SPE microfluidic device successfully enables in-line monitoring of the release profiles in a permeation assay. Highlighting its potential for drug delivery and pharmaceutical development.