我們利用Tresyl monomethoxy polyethylene glycol (TM-PEG) 與free lysine的PEGylation反應，探討其動力學模式，利用螢光分析及作圖法，估計出TM-PEG及Lysine於PEGylation反應中的反應級數分別為1.69及1.09，同時並以Arrhenius學說為基礎，推論PEGylation反應的活化能，進而探討反應對溫度的敏感性。

在了解反應物濃度、溫度及時間對PEGylation反應的影響後，將此結果應用於重組腺病毒的PEGylation反應，藉由提昇反應物濃度，以降低反應的時間，同時配合添加少許的蔗糖 (5 %)，可以改善因PEGylation反應造成病毒活性大幅流失的現象。雖然，經過PEGylation反應後的腺病毒依然有活性的流失，但PEGylation卻提昇了病毒的穩定性，根據結果顯示，在37 ℃環境下平均約每小時流失1個 log 值的活性，降低至約每小時 0.5-1個log 值的活性流失。而在4 ℃的溫度下，由一天1.5 log 值左右的喪失活性，減少至一天 1 個 log值以內的活性喪失。

We studied the kinetics of PEGylation by observing the conjugation reaction between tresyl monomethoxy polyethylene glycol (TM-PEG) and free lysine. We employed a fluorescence assay and graphic methods to determine the reaction orders with respective to TM-PEG and lysine. According to the experimental results, the reaction orders of PEG and lysine are 1.69 and 1.09, respectively. We also determined the activation energy of PEGylation using Arrhenius’ theory and discussed the temperature sensitivity of PEGylation.

The reaction kinetics was applied to optimize that PEGylation reaction to modify adenovirus. By raising reactant concentrations and with the addition of 5 ﹪sucrose in the reaction mixture, the loss of adenoviruses titer during PEGylation process could be reduced. Although adenovirus titer was reduced during PEGylation, PEGylated adenovirus exhibits better stability under harsh storage conditions. Our results showed that there was approximately 0.5 to 1 log loss of the original titer in PEGylated adenovirus per hour at 37℃ whereas there was at least 1 log per hour reduction in viral titer when non-PEGylated adenovius was incubated at 37℃. Similarly, PEGylated adenovirus is more stable than non-PEGylated adenovirus at 4 ℃; the rate of titer loss is 1.5 log/day and 1.0 log/day for non-PEGylated and PEGylated adenoviruses, respectively.

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