本研究的目的在於開發出一套能夠以高靈敏度以及高精度做腸道寄生蟲快速診斷的系統。本系統主要整合了智能手機顯微鏡以及手持式離心設備，主要應用於資源匱乏的地區做及時檢測。土壤傳播的蠕蟲是一大類寄生蟲，主要盛行於衛生條件差且沒有乾淨水源之發展中國家。目前寄生蟲標準的診斷最常用的方法（直接塗片方法）雖然成本低廉且相對容易執行，然而主要缺點為偽陰性結果很高。相對高靈敏度的檢測方法 如離心檢測法需要昂貴，笨重的設備，如搖擺式離心機和顯微鏡。在資源有限的開發中國家這些設備都不容易取得以及維護。因此在本研究中，開發了一種手動驅動的微流體離心裝置，用於濃縮與計算糞便樣品中寄生蟲卵的數量，同時使用智能手機與顯微鏡鏡頭配對，通過智能手機上的圖像處理對寄生蟲感染進行檢測和定量。經由我們的初步結果限顯示，我們這套檢測系統可以檢測和量化來自糞便樣品的多種寄生蟲，其最低檢測濃度理論值可達20個蛋/克，超過了當前台式方法的靈敏度。此外，該系統作離心濃縮寄生蟲蛋只須2~3分鐘，且回收率高達95% 。該平台可望能提供比當前方法更可靠的糞便感染評估，並且可以在資源有限的環境中使用。

This study presents a centrifugal device coupled with a smartphone microscope capable of rapidly diagnosing intestinal parasitic infections with high sensitivity and accuracy. Soil transmitted helminths (STHs) are a family of parasitic worms found primarily in developing countries with poor sanitation and limited access to clean water. The most common method for STH diagnosis (such as direct smear or Kato Katz methods), though low cost and relatively easy to perform, still suffer from high false-negative results, while active floatation methods require expensive, bulky equipment such as swing bucket centrifuges and microscope, which is typically not accessible in resource-limited regions. In this study, a hand-driven microfluidic centrifuge device for active concentration of parasitic eggs within fecal samples was developed, while using a smartphone paired with a microscope lens to perform image acquisition and analysis. To the best of our knowledge, this is the first time an all-in-one point-of-care system capable of performing parasite egg concentration and smartphone imaging has been demonstrated. Our experimental results suggested that the system could detect and quantify parasites from fecal samples at levels as low as 20 eggs/gram which exceeds the sensitivity of current bench-top methods. Also, the centrifugation process to concentrate parasite eggs to the center of the device only take 2~3 minutes to complete with a 95% recovery rate. This platform may provide a more reliable assessment of fecal infections than the current approach and can be used in resource-limited settings.

Chapter 1 Introduction................................................1
1.1 Motivation...........................................................1
1.2 Parasitology.........................................................2
1.3 Common types of soil-transmitted helminths...........3
1.3.1 Paragonimus westermani....................................3
1.3.2 Taenia spp. .......................................................3
1.3.3 Ascaris lumbricoides.........................................4
1.3.4 Toxocara canis.................................................5
1.4 Current methods for diagnosing STH infections .......6
1.5 Motivation and novelty........................................6
Chapter 2 Materials and Methods ...............................9
2.1 Experimental setup..............................................9
2.2 Chip design........................................................11
2.3 Centrifugal chip fabrication..................................17
2.4 Preparation of floatation solution..........................19
2.5 C. elegans culture and egg extraction.....................21
2.6 Harvesting parasite eggs.......................................21
Chapter 3 Results and Discussion................................24
3.1 Evaluation of smartphone microscope resolution....24
3.2 Centrifugation viability test using spin coater.........24
3.3 Viability test of hand-driven centrifugation............24
3.4 Measuring spin speed of hand-driven centrifuge ......25
3.5 Measurements of egg recovery (Toxocara Canis) after centrifugation....42
Chapter 4 Conclusion and Future perspectives................45
4.1 Compare with current methods including McMaster and FLOTAC techniques......46
4.2 Automatic image capture and analysis implementing computer vision..................46
Chapter 5 References..........................................48

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