昆蟲桿狀病毒（baculovirus）已於1995年證實可感染哺乳動物細胞，因此被認為具有成為基因治療載體的潛力。若要將其應用在基因治療載體方面，先決條件是取得高純度及高濃度之桿狀病毒。傳統的多次超高速離心純化法因相當費時費力且較難以規模放大，並不適合作病毒載體的大量純化。相對地，層析法已廣泛應用於蛋白質純化 但尚未普遍應用於基因治療載體之大規模純化。因此，本實驗室先前應用固定化金屬親合力層析法(IMAC)結合超過濾(ultrafiltration)系統純化桿狀病毒，在IMAC部分回收率可達8 %。為提升回收率以使此結果可以應用至大規模純化，在本研究中針對IMAC及超過濾系統的各項參數予以改進，這些參數包含IMAC進料流速(提升病毒結合速率並縮短操作時間)，IMAC溶液鹽度(提升病毒結合速率並減低對病毒傷害)，IMAC溶液pH值(提升病毒結合速率並減低對病毒傷害)，IMAC沖提液梯度(提升純化效率)，超過濾濾膜孔徑(提升前處理效率)以提升回收率及純度等。並以終點稀釋法(EPDA, End Point Dilution Assay)及流式細胞儀作為監測每一純化步驟病毒回收率的工具，希望能找出適當的純化步驟。

Baculovirus has been proved to be able to infect mammalian cells at 1995 and have the potential as a gene delivery vehicle. As a gene therapy vector, generation of high viral purity and concentration is prerequisite. Traditional virus purification by several ultra centrifugations is not suitable for virus purification on large scale, because it is time consuming and hard to scale up. Comparatively, chromatography has been widely used on protein purification but has not been widely used on mass purification of gene therapy vehicle. In precious research of our laboratory, we combine immobilized metal affinity chromatography (IMAC) and ultrafiltration system to purify baculovirus, and the recovery of virus titer is 8 % in IMAC process. To apply this result for purification on large scale, we should improve virus recovery. In this research, we try to modify parameters of IMAC and ultrafiltration, such as feed flow rate of IMAC (to improve virus combining rate and shorten operating time), salt concentration of IMAC buffers (to improve virus combining rate and shorten operating time), pH of IMAC buffers (to improve virus combining rate and shorten operating time), gradient of IMAC elution buffer (to improve purification efficiency), and pore size of ultrafiltration membrane (improve ultrafiltration efficiency) to improve recovery and purity. We try to find applicable purification process by using End Point Dilution Assay (EPDA) and flow cytometry to detect virus recovery in each step of purification process.

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張耀仁，非溶裂桿狀病毒表現系統之研究（2002），國立清華大學化學工程研究所碩士論文。
蔡建泰，利用固定化金屬親合力層析法純化基因重組昆蟲桿狀病毒（2003，國立清華大學化學工程研究所碩士論文。