CHINESE ABSTRACT Major urinary proteins(MUPs)是一種由老鼠肝臟分泌的蛋白質,經過腎臟的過濾後,只會存在於成年公老鼠的尿液當中,MUPs的分子形狀是利用8個-barrel 包成的疏水性袋狀結構,而MUPs會用其疏水性袋狀結構和有氣味的天然小分子進行鍵結並加以濃縮,其鍵結親合力在104~105 M-1之間。其可藉由氣相層析儀或質譜儀描繪出這種緩慢釋放氣體的特性,不過,這些方法卻無法直接的觀察到整個鍵結反應的過程。隨著科技的進步,近年來出現了一種能檢測微小質量變化的石英壓電微量天平之儀器,是利用石英晶片金電極表面的重量變化會影響震盪頻率的原理。 因此本研究設計以MUPs為氣體分子之接受器,搭配上作為訊號轉換元件的QCM,藉以觀察MUPs和氣體分子鍵結的過程,以及研究MUPs的一些基本性質,實驗中發現MUPs能在五秒內與檢測品反應,不會受曾浸泡酒精之影響而失去活性,能在4℃的保存環境下保存十一個月後仍具功效,並能與29種標準品反應。未來可以利用QCM來快速測定經遺傳工程改變的MUPs之氣體吸附特性。
ENGLISH ABSTRACT Major urinary proteins (MUPs) are proteins secreted by mice liver. After the filtration of kidney, these proteins only existed in the urine of mature male mice and rats. MUPs are hydrophobic pocket structure formed by eight β-barrels. Nature flavor molecules were bound by these hydrophobic pocket structures of around 104~105 M-1 binding affinity and also were concentrated. These gas-releasing properties could be analyzed by gas chromatography and mass spectrometer but the binding mechanism could not be directly observed by these methods. According to technology evolution, quartz crystal microbalance (QCM) that detects the micro-mass changes was invented. The principles of this equipment were detecting the vibration frequency caused by the mass variation on the gold electron coated quartz crystal. In this study, MUPs were made to be the accepters of flavor molecule. Along with the QCM as the transducer, the binding processes as well as the basic property of MUPs and flavor molecule were observed. MUPs were reacted with the samples in 5 seconds and didn’t loss its activity after soaked in ethanol. It retained its functions after store at 4℃ for 11 months and could be used to detection 29 standard samples. In the future, the gas adsorption of genetically modified MUPs can be detected by the QCM system.