本研究成功的以微滲透式系統進行蛋白質結晶條件的快速篩選，利用滲透作用，每單位體積的蛋白質樣品可被用來在更大範圍的濃度與速度參數值中篩選出結晶條件，如此將有效降低蛋白質樣品的需要量。這些功能是利用半透膜控制滲透作用所達成，藉由驅動並控制水份離開蛋白質溶液的速度以調整蛋白質溶液的濃度與其改變率，進行快速且可機動調整的蛋白質結晶條件篩選。這套蛋白質結晶條件篩選系統的雛型 (6×8陣列，6個獨立參考溶液流道，長24mm、寬20mm、厚度2.5mm) 主要是以高分子板材與半透膜為材料所製成，並藉由熱壓與熱熔所組裝而成。到目前為止，這套系統已經成功應用在四種不同的蛋白質，包括Lysozyme、Catalase、Thaumatin及Xylanase的分析，每單位蛋白質樣品的體積為400nl。測試結果顯示可以在1-3小時內篩選出蛋白質結晶的適當條件，除此之外，利用此系統可長出大小超過100μm的蛋白質晶體，品質足以提供X光繞射儀進行繞射分析，產生足以反解出蛋白質結構的資訊。如此一來，這套微滲透式篩選系統將可做為一個創新並具有高效能的蛋白質結晶條件篩選系統。

This work presents a micro osmotic screening system that grows protein crystals in hours with microgram samples. In each crystallization cell, water is driven in or out of a protein solution (across a semi-permeable membrane) to adjust its concentrations. Employing the bi-directional flow control realized by osmosis, each protein sample can be screened for crystallization conditions over highly extended ranges. In the prototype demonstration, 6 x 8 arrays with an overall size of 20 x 24 x 2.5 mm3 are fabricated and tested in the crystallization experiments. Crystallization conditions for lysozyme, catalase, thaumatin, and xylanase are identified within 1 to 3 hours while consuming less than 20 μl of protein solution each. Furthermore, it is also demonstrated that diffraction-quality crystals may be grown and harvested from the prototype systems. As such, this osmotic system pioneers a new class of rapid screening schemes for high-through- put protein crystallization.

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