有機無機複合矽基材之製備及其生化應用於生物感測器與癌症化學治療

Abstract

矽溶膠凝膠已被廣泛應用於生物分子固定化於各種工業上的應用。但由於溶膠凝膠本身固有的機械剛性和結構維持特性而使得其應用有所限制。因此在本研究中將利用有機無機複合矽基材來進行生物酵素的固定化及其應用於生物感測器製備及癌症化學治療之可行性進行評估。在這個研究中，我們首先利用經聚二甲基矽氧烷改質後之有機無機複合矽基材(TEOS/PDMS)來進行酵素固定化。所製備出的有機無機複合矽基材具高透明度和無裂紋之特性。包覆於TEOS/PDMS有機無機複合矽基材的酵素能夠保留其自身活性長達二個月之久。為了了解此一基材應用於生物感測器之可行性，將製備一包覆葡萄糖氧化酵素於TEOS/PDMS有機無機複合矽基材的鈀電極並利用循環 伏安法與計時電流法針對其電化學特性進行分析。經實驗發現該一生物感測器具有寛廣的檢測範圍和高重複性等良好性能。 結合TEOS/PDMS有機無機複合矽基材與CMOS感測晶片來製備出過氧化氫及葡萄糖光學感測器之可行性亦進行研究。令人興奮的是，經山葵過氧化酵素催化luminol所產生之生物冷光可以在光學過氧化氫生物感測器中進行即時檢測。光學過氧化氫和葡萄糖生物感測器器製備後皆針對其操作溫度、pH值及感測線性範圍作最適化條件之探討。這些結果展現出以CMOS的光電二極管為基礎之光學生物感測器具有很多優點，如檢測時間短、要求的樣本量小、高度再現性和寬廣的動態感測範圍。 此外，一種新型的包覆酵素之有機無機複合矽納米粒子(ESNP)是利用TEOS/PEG有機無機複合矽基材所生成，其平均粒徑大小為70 ± 1.43納米。包覆在ESNP的山葵過氧化酵素(HRP-SNP)展現出類似游離酵素之生物特性。利用HRP-SNP於前趨藥物癌症治療的可性行亦進行特性研究。這些結果表明出所研發之ESNP在應用前藥物治療癌症上具有很大的潛力。

Silica xerogel was widely used in the immobilization of biomolecules for various industrial applications. Unfortunately, the application of silica xerogels in the protein immobilization is limited due to their poor mechanical properties and structural maintenance. Therefore, the feasibility of organic-inorganic hybrid silica materials in the immobilization of enzymes and its applications in biosensor design and cancer chemotherapy were investigated. The poly(dimethylsiloxane)-modified silica sol-gel (TEOS/PDMS Ormosil) glass was first developed in this study for the immobilization of enzymes. The synthesized TEOS/PDMS Ormosil monoliths exhibited high transparency and crack-free. The enzyme encapsulation in the TEOS/PDMS matrixes can retain its most of activity for at least two months. The enzyme electrode based on glucose oxidase encapsulated TEOS/PDMS Ormosil glass on Pd electrode was fabricated and characterized. The electrochemical properties of the fabricated glucose biosensor were studied by cyclic voltammetry and chronoamperometry. The electrochemical response of the fabricated glucose biosensor exhibits wide dynamic range detection and high reproducibility. The availability of highly transparent TEOS/PDMS Ormosil in the development of biosensor for detection of H2O2 and glucose was also demonstrated by fabricated of CMOS-base optical biosensor. Interestingly, HRP-catalyzed luminol luminescence can be detected in real time on the fabricated H2O2-biosnesor. Both optical H2O2 and glucose biosensors were developed and characterized by their temperature and pH-dependant operation and the linear dynamic range of detection. The CMOS-photodiode-based optical biosensors proposed herein have many advantages, such as a short detection time, a small sample volume requirement, high reproducibility and wide dynamic range. A novel enzyme-encapsulated silica nanoparticle (ESNP) was also developed by using TEOS/PEG with an average size of 70 ± 14.3 nm. The generated horseradish peroxidase encapsulated in silica nanoparticle (HRP-SNP) exhibits several biological properties similar to that of free enzymes. The feasibility of using HRP-SNP in prodrug cancer therapy was also promptly investigated. The results obtained in this study indicate that the developed ESNP has great potential in prodrug cancer therapy applications.

KEYWORDS: Enzyme Encapsulation, TEOS/PDMS, TEOS/PEG, Prodrug Cancer Therapy, Sol-Gel, CMOS-base Optical Biosensor, Ormosil, Organic-Inorganic Hybrid Silica Materials