自組單層分子膜固定於壓電晶體上用以定量分析人類血清白蛋白

Self-Assembled Monolayer-Based Piezoelectric Crystal Immunosensor for the Quantification of Human Serum Albumin

黃淑鈴(Shu-Ling Huang)

指導教授 ： 鍾相彬 ； 趙垂勳

高雄醫學大學/醫學院/醫學研究所/碩士(2004年)

摘要

石英微質量天平是壓電晶體感測器的一種，其原理為材料學中的逆壓電效應：即石英晶體電極表面質量的變化量與晶體振盪頻率變化量間會呈正相關。由於靈敏度相當高，近幾年來，在生物醫學上，常應用於電極表面抗原-抗體免疫結合後的質量改變，以進行免疫分析。石英微質量天平的本體為石英晶體上附著金屬電極片（通常為金或銀，本研究的材料是金），將抗體固定於於電極上以製成免疫電極，為方便固定化抗體，需在金電極表面修飾上一層介面物質當作連接物。本研究選用11-mercaptoundecanoic acid(11-MUA)自組單層分子膜(self-assembled monolayer；SAM)當作連接物，再將Anti-HSA(Anti- Human Serum Albumin)固定於金電極上，以製成測量HSA的免疫電極。
研究中以X光光電子能譜儀(X-ray photoelectron spectroscopy；XPS)、接觸角度量(contact angle measurement)及傅立葉紅外線光譜(Fourier-transformed infrared spectroscopy；FTIR)研究自組單層分子膜(SAM)附著於金表面的物性與化性。使用同位素碘-125標誌HSA及Anti-HSA探求固定化的最佳條件，及免疫反應的各個相關參數。可藉由此條件製成的免疫電極測量不同濃度的抗原造成頻率變化之間的關係。
由光譜及接觸角可確認自組單層分子膜附著於金電極表面的結果，而在最佳抗體固定化條件下所製成的免疫電極其頻率變化和抗原濃度之間成正相關(R2=0.8763)，可量測抗原濃度於1μg/ml~1000μg/ml間，此測量範圍在實用範圍內，亦證明本方法之實用性。
在此研究中，使用HSA及Anti-HSA及SAM所建立的相關技術及研究平台，提供日後研究其他免疫電極的最佳環境。

關鍵字

免疫感測器 ； 自組單層分子膜 ； 壓電晶體

並列摘要

The quartz crystal microbalance, one of piezoelectric crystal biosensors is used as the transductor to analyze microelement in term of its physical properties. According to the inverse piezoelectric effect, mass change in quartz crystal microbalance is postive correlated to the oscillation frequency change of quartz crystal. Through the high sensitivity, the mass change in quartz crystal microbalance that is due to the immunoreaction is recently used for the immunoassay in biomedicine. The metal-plated electrode of the quartz crystal provides a surface to modify a suitable recognition. The metal can be gold, silver or others. In this study, we choose the gold-plated electrode and then the antibody is immobolized onto it. Self-assembled monolayer (SAM) is used as the linkage to immobilize the antibody more firmly onto the gold electrode of the quartz crystal. In this study, 11-mercaptoundecanoic acids (11-MUA), one kind of SAM is applied to immobilize anti-HSA (Anti-Human Serum Albumin) for the quantification of the HSA (Human Serum Albumin).
X-ray photoelectron Spectroscopy (XPS), contact angle measurment and Fourier-transformed infrared spectroscopy (FTIR) are used to investigate the physics and chemical property of the 11-MUA deposited on the gold-plated electrode of the quartz crystal. Iodine-125 labeled anti-HSA and HSA are used to search the optimal conditions and methods for the immobilization and immunoreaction. The relationship between the frequency change and the concentration of antigen is displayed by the immunosensor produced by the optimal conditions.
The results of the spectroscopy and contact angle confirm that the 11-MUA is deposited on the gold-plated electrode of the quartz crystal. The frequency change measured by the immunosensor that is produced under the optimal antibody immbolization is postive correlated to the antigen concentration between 1μg/ml and 1000μg/ml (R2=0.8763). The detectable range of the antigen concentration is practical. In this study, the techniques of the SAM and the immobolization of protein provide platforms for the development of related fields.

並列關鍵字

Immunosenssor ； SAM ； QCM

參考文獻

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