蛋白質被普遍用於日常生活中，人體內促進生長發育的生長賀爾蒙、糖尿病的治療劑胰島素、食品烘焙用澱粉脢及洗衣粉中的分解酵素等皆是由蛋白質所組成。蛋白質不論是用在結構分析預測或醫療藥品上，純化的要求都相當嚴格，不但要避免副作用產生更要注意使用者的安全。蛋白質超過濾操作的主要功用包括蛋白質濃縮、雜質去除及純度提高。截至目前為止，工業界仍無法完全掌握整個超過濾過程的細節，通常是就各別影響因素加以控制並過濾後，適時調整操作參數，以逐步取得要求的純度及數量，過程既繁瑣又難精確。為了達成對蛋白質純化能力的掌控，本研究以微觀模型探討及模擬整個超過濾製程之重要參數及作業行為，改善其盲點並達成蛋白質純化的最終目標。
本研究以微觀分子力學模型為基礎，探討超過濾製程之重要參數，並以此建構一套完整的超過濾理論模型。首先利用分子力學推估介質參數，並完成含多種交互影響因素之超過濾巨觀模型。接著將巨觀模型微觀化，再進行電腦模擬，藉由分子力學模擬掌握微觀粒子(包括原子、分子等基本粒子)的運動狀態，以探討原子與分子所組成的蛋白質在超過濾作業中之物理性質及物系總體行為。最後，將文獻實驗資料與微觀模擬結果相互印證，並以印證後可靠之模型進行超過濾產量預估及優化等應用。
由本文所提之複合超過濾理論估算值與文獻實驗資料值相互比對之結果，發現兩者間誤差均落於6 %內，證實本文所提之理論精確可行。製程介質參數的取得，若採用本文所提之分子動力模擬法進行推估，可改善現有既耗時又不經濟的重覆實測之方式，大幅提高生產之效率。此外，本研究所建構之超過濾成果推估電腦演算系統，對超過濾行為預估及最佳化等應用，有相當大的助益。未來更可將該套理論推廣使用於其他各種生化技術、生醫工程、電子工業及食品工業等領域。

Proteins are commonly used in daily life for various purposes including (1) the hormone of growth for human body, (2) the insulin for treatment of diabetes mellitus, (3) the amylase for food bakery products, (4) the decompose enzymes used in washing powders. In order to avoid detrimental end effects for patients, the demand on protein purification is very strict. The functions of ultrafiltration process include protein condensation, impurities removal and purity enhancement. Traditionally, the ultrafiltration process is done by changing influential factor one at a time. The operating parameters are adjusted based on the results of each experimental run so that the requirements on both purification degree and overall output can be met. In order to characterize the ultrafiltration process both of the macroscopic and microscopic modeling approaches will be employed in this project.
This project will finally establish a comprehensive ultrafiltration model for protein purification. The comprehensive model will integrate all intermolecular reaction forces, external operating forces and membrane resistance forces together. The microscopic molecular dynamics approach will then be used to estimate key physical parameters and to characterize the behaviors of comprehensive ultrafiltration processes for protein purification in microscopic viewpoint. The results will then be further verified by experimental data.
The computed results obtained from the study are compared with experimental ones in the literature. It was found that the results obtained by the proposed method and those appeared in the literature agree quite well.

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