數十年來，肝病一直列在國人十大死亡因素之中，相關藥物的開發、測試，一直都是醫藥科學發展的重點。一種藥物從開發到達上市，需要歷經無數次的實驗測試，以確保藥物的安全性以及有效性。因此，藥物實驗平台的開發成為近幾年生物醫學研究發展的重點之一。
而傳統醫學的研究又可以分為體內研究以及體外研究來進行，生物的活體內研究雖然擁有與真實生物體較高的相似度，可以比較真實反映出生物體對藥物所出現的反應，同時也因為生物個體因為複雜度高，如需針對特定反應做觀察、研究，相對較不易，且使用活個體進行實驗較容易會有法律以及道德層面的問題。而體外研究的優點就是可以針對欲研究的目標創造一個模擬的生物環境，其環境可以經由人為控制，相較之下單純許多，容易用來進行研究及觀察，只是其與生物體的功能性差異，也是各項研究所要努力克服的目標。
本研究中提出利用微流體晶片技術以及細胞操控技術，設計晶片以製造出更接近於真實人體組織的體外組織晶片為目標。本研究所提出的體外仿肝組織循環系統晶片包含了二個重要的特色：(1)利用介電泳細胞操控技術，操縱數種細胞於不同的晶片區域中，製成模仿血管環境的血管晶片區域以及模仿肝的放射狀肝小葉組織的晶片區域；(2)利用微流體晶片的設計，建立一仿肝小葉流場，並且模仿體內肝組織體液循環的順序，建立一完整的體外仿肝循環系統實驗室晶片。
經由肝功能尿素檢測實驗結果顯示，此系統所提供的微環境，其中包含血管環境、肝組織、肝小葉流場，能夠成功提升肝細胞的尿素分泌表現量達78%。目前為止，仿肝組織循環的研究鮮少被提出，此研究的目標希望以體外重建工程，建立一仿肝實驗室晶片，使其越接近於人體真實肝組織環境，並且期望可以應用於藥物篩選、檢測的應用中。

In the past decade, liver disease has been one of the top ten death causes. Medical science researchers have focused on the development and testing of required drug. The effective functioning and safety of a new developed drug must be ensured via numerous experiments before reaching the market. Therefore, the developments of drug experiment platform become the focal point of biomedical research in recent years.
Conventional biomedical studies are carried out either in vivo or in vitro. In vivo research utilizing intact organisms can provide high resemblance to the real physiological conditions. However, the variations in experimental results are relatively high due to the high complication of organisms and the great diversity of entities. It is also difficult to observe the biological processes in whole organisms. The problems of laws and morality must also be considered. However, the advantage of in vitro studies is that the simulated biological environment can be created depending on the research target. The environment can be controlled and it is easier to observe and manipulate. But it is unable to reflect the complex physiological responses found in vivo.
In this research, we propose an in vitro liver circulatory system via the concept of cell pattern technology and microfluidic system. There are two features of the proposed liver Labchip: (1) Mimicking the condition of blood vessel and liver-lobule-mimetic engineered tissue. To achieve this we have manipulated four kinds of cells in two different bio-chambers via DEP cell patterning technology. (2) Mimicking the circulatory system and condition of blood flow in the liver lobule. To accomplish this two bio-chambers were connected via the lobule-flow-mimic microchannel. The experimental results reveal that the liver-specific function, urea secretion of this proposed in vitro liver circulatory system show 78% of enhancement when compared with absent liver circulatory system. In recent years, only few researchers made an attempt to combine the engineered liver tissue with a liver circulatory-like fluidic system. The proposed research shows some exciting initiative results in liver tissue reconstruction. The ultimate goal of the present research is to construct in vitro liver tissue and make it closer to the actual liver functioning. This research will be an useful tool for developing platform of drug testing and screening.

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