(1)分子信籤應用於螢光感測酵素活性與其抑制； (2)開發新的合成方法製備金奈米簇

聶之鈞

18.207.108.182，Hello！

Close
Search Quick Search Advanced Search Publication Search	Personal Service Member Login Searching History Use Bonus Card SYMSKAN
Browse Browse by University of Graduate Thesis Browse by Pinyin of Graduate Thesis Browse by Conference Proceedings Topic Browse by Conference Proceedings Publisher Browse by Pinyin of Conference Proceedings Browse by eBook Category Browse by eBook Topic Browse by eBook Publisher
Customer Services Authorize Airiti Recommend a Journal

Search Symbol (Half-width)	Description of Search Symbols
Space	"AND" indicates the intertwining of key terms used in a search
Double Quotation Marks ("") ( " " )	Double quotation marks indicate the beginning and end of a phrase, and the search will only include terms that appear in the same order of those within the quotations. Example: "image process" ： " image process "
?	Indicates a variable letter. Entering two ? will indicate two variable letters, and so on. Example: "Appl?", search results will yield apple, apply… e , appl y … ( (often used to English word searches) )
*	Indicates an unlimited number of variable letters to follow, from 1~n. Example: Enter "appl*", search results will yield apple, apples, apply, applied, application…(often used in English word searches) e , appl es , appl y , appl ied , appl ication … ( (often used to English word searches) )
AND、OR、NOT	Boolean logic combinations of key words is a skill used to expand or refine search parameters. (1) AND (1) AND: Refines search parameters (2) OR (2) OR: Expands search parameters (3) NOT: Excludes irrelevant parameters

DOI stands for Digital Object Identifier （ D igital O bject I dentifier ） ,
and is the unique identifier for objects on the internet. It can be used to create persistent link and to cite articles.

Using DOI as a persistent link

To create a persistent link, add「http://dx.doi.org/」「 http://dx.doi.org/ 」 before a DOI.
For instance, if the DOI of an article is 10.5297/ser.1201.002 , you can link persistently to the article by entering the following link in your browser: http://dx.doi.org/ 10.5297/ser.1201.002 。
The DOI link will always direct you to the most updated article page no matter how the publisher changes the document's position, avoiding errors when engaging in important research.

Cite a document with DOI

When citing references, you should also cite the DOI if the article has one. If your citation guideline does not include DOIs, you may cite the DOI link.

DOIs allow accurate citations, improve academic contents connections, and allow users to gain better experience across different platforms. Currently, there are more than 70 million DOIs registered for academic contents. If you want to understand more about DOI, please visit airiti DOI Registration （ doi.airiti.com ）。

Data Source

Basic & Applied Sciences > Chemistry
College of Science > Department of Chemistry

Bibliography Management Tool

Related Links

Report an Issue

Search in Library

There is no full-text available at the moment. Airiti would like to request author's authorization. I would like to provide authorization.

(1)分子信籤應用於螢光感測酵素活性與其抑制； (2)開發新的合成方法製備金奈米簇

(1) Molecular beacon for fluorescent assay of enzyme activity and its inhibition; (2) A new strategy for preparing gold nanoclusters

聶之鈞 , Masters　　Advisor：曾韋龍　　

繁體中文

榖胱甘肽；金奈米簇；腺苷； S-腺苷-L-高半胱胺酸水解酶；分子信籤；螢光； fluorescence ； glutathione ； S-adenosylhomocysteine hydrolase ； gold nanocluster ； adenosine ； Molecular beacon

Abstract │ Reference (76) │ Altmetrics

Abstract 〈TOP〉

本篇研究分為兩部份：設計分子信籤 (Molecular beacon)，分別在5''和3''以共價鍵結修飾螢光團和消光團，當加入分析物後可誘導分子信籤構型改變，產生螢光訊號的差異，藉此應用於偵測酵素及其抑制；開發新的合成方法合成金奈米簇，利用其具有的特殊光學性質與化學性質，應用於偵測胺基酸硫醇、葡萄糖及催化反應。
(一) 分子信籤應用於螢光感測酵素活性與其抑制：
S-腺苷-L-高半胱胺酸水解酶 (SAHH)，此酵素活性可調控胺基硫醇類代謝物的含量，在細胞中扮演重要的角色，且與免疫不全疾病及遺傳性甲硫胺酸代謝障礙有密切關係。另外，當SAHH活性被抑制時，細胞內SAH濃度升高，間接干擾生物體內酯類、蛋白質、核酸的甲基化進行，影響細胞之代謝。依此原理設計有效抑制SAHH酵素活性之藥物可用於寄生蟲疾病的藥物使用。因此，本篇研究設計一分子信籤，Loop端含有15個鹼基，Stem端含有8個胸腺嘧啶 (Thymine, T)鹼基，並於5''和3''端分別修飾上螢光團 (HEX)和消光團 (DABCYL)，透過Non-Watson-Crick配對方式，形成金屬-鹼基鍵 (T-Hg2+-T)，使分子信籤形成髮夾彎 (Hairpin)結構，造成螢光團與消光團互相接近產生碰撞消光，而螢光下降，此時為T8-MB．Hg2+ probe。當含有胺基硫醇分子時，因Hg2+-S間具有強共價作用，能將分子信籤內的Hg2+置換出來，使分子信籤的髮夾彎結構改變，形成任意捲曲狀 (random coil)造成螢光恢復，利用螢光回復來針對高半胱胺酸及酵素定量，線性範圍分別為10~100 nM及12.5~125 units/mL，偵測極限為3 nM及4 units/mL (0.24 nM)；當腺苷類似物存在時，可有效地抑制SAHH活性，降低或停止催化SAH水解反應，致使分子信籤探針的構形不改變而無螢光信號回復的現象。此設計也成功應用於偵測乙醯膽鹼酯酶水解硫代乙醯膽鹼的反應。
 
(二) 開發新的合成方法合成金奈米簇：
	近年來發展出許多合成奈米簇的方法，主要可分為兩大類：下到上 (botton-up)及上到下 (top-down)的合成路徑。在本篇研究中提出一個新的合成方法來獲得金奈米簇，並於中性條件下利用蛋白質做為模板及具有size-focusing的特性，將外界水相隔絕，減少非螢光途徑的能量緩解，降低螢光淬熄的機會，合成出一系列不同放射波長的螢光金奈米簇。利用金奈米簇的特殊光學性質與化學性質，開發出功能性金奈米簇配合分析上的各種應用。由於結構的特性，Au5及Au8金奈米簇會受到胺基酸硫醇的core-etching造成螢光淬熄，利用此現象來偵測榖胱甘肽，並進行定量分析；過氧化氫具有強氧化性，當其與金奈米簇反應，會造成奈米簇表面特性改變造成螢光淬熄，我們利用葡萄糖氧化酶作為模版，合成出綠色螢光金奈米簇，藉由催化葡萄糖生成過氧化氫，對葡萄糖進行定量分析。最後利用金奈米簇催化對-硝基苯酚生成對-安基苯酚，此結果說明金奈米簇具有催化能力。

Parallel Abstract 〈TOP〉

The thesis consists of two parts. In the first part, we present that a thymine (T)-based molecular beacon (MB) is used for probing S-adenosylhomocysteine hydrolase (SAHH)-catalyzed hydrolysis of S- adenosylhomocysteine (SAH), and for following the inhibition of SAHH. The designed MB (T8-MB-T8) contains a 15-mer loop and a stem consisting of a pair of 8-mer T bases, a fluorophore unit at the 5''-end, and a quencher unit at the 3''-end. When Hg2+ induced T-T mismatches to form stable T-Hg2+-T coordination in the MB stem, a change in the conformation of T8-MB-T8 places fluorophore and quencher in proximity to each other and causes in the collisional quenching of fluorescence between them. SAHH catalyzed the hydrolysis of SAH to produce homocysteine. The generated homocysteine enables Hg2+ to remove from a hairpin-shaped T8-MB-T8 through the formation of strong Hg2+-S bond, leading to the restoration of its fluorescence. The T8-MB-T8.Hg2+ probe showed a limit of detection for SAHH of 4 units L-1 (～0.24 nM) and is reusable for detecting the SAHH/SAH system. Because adenosine is effective to inhibit SAHH activity, the T8-MB-T8.Hg2+ probe combined the SAHH/SAH system was used for sensitive and selective detection of adenosine in urine and serum without the interferences of other adenosine analogues. 
In the second part, we developed a new strategy for the production of gold nanoclusters based on the fact that fenton reaction is capable of inducing etching of gold nanoparticles. This top down-based synthesis of gold nanoclusters follows two steps: (1) in the presence of glutathione, reduction of the Au3+ precursor solution with NaBH4 resulted in the formation of gold nanoparticles and (2) the formed gold nanoparticles was etched to gold nanoclusters via Fenton reaction. To obtain atomically precise gold nanoclusters and enhanced their quantum yields, different types of proteins were used for size focusing of the formed gold nanoclusters. The maximal emission of trypsin-, bovine serum albumin-, lysozyme type VI-, and glucose oxidase-stabilized gold nanoclusters appears at 415, 463, 460, and 535 nm, suggesting the presence of Au5, Au8, Au8, and Au13 clusters, respectively. (Matrix-assisted laser desorption/ionization)-(time-of-flight) mass spectrometry and slab-gel native electrophoresis were utilized to demonstrate the formation of gold nanoclusters. Because glutathione can efficiently etch trypsin-stabilized Au5, bovine serum albumin-stabilized Au8, and lysozyme type VI-stabilized Au8, these clusters were well suited to probe glutathione. Glucose oxidase-functionalized Au13 clusters were utilized to detect glucose via the combination of glucose-glucose oxidase catalyzed reaction and H2O2-induced quenching of gold nanoclusters. In addition to the application of gold nanoclusters as optical sensors, we disclose that gold nanoclusters as catalysis for conversion of 4-nitrophenol to 4-aminophenol were more efficient than glutathione- and citrate-capped gold nanoparticles.

Reference ( 76 ) 〈TOP〉

2. Marras, S. A., Interactive Fluorophore and Quencher Pairs for Labeling Fluorescent Nucleic Acid Hybridization Probes. Mol. Biotechnol. 2008, 38, 247-255.
連結：
3. Lin, Y. H.; Tseng, W. L., A room-temperature adenosine-based molecular beacon for highly sensitive detection of nucleic acids. Chem. Commun. 2012, 48, 6262-6264.
連結：
4. Bourdoncle, A.; Torres, A. E.; Gosse, C.; Lacroix, L.; Vekhoff, P.; Le Saux, T.; Jullien, L.; Mergny, J. L., Quadruplex-Based Molecular Beacons as Tunable DNA Probes. J. Amer. Chem. Soc. 2006, 128, 11094-11105.
連結：
5. Yang, R.; Jin, J.; Long, L.; Wang, Y.; Wang, H.; Tan, W., Reversible molecular switching of molecular beacon: controlling DNA hybridization kinetics and thermodynamics using mercury(ii) ions. Chem. Commun. 2009, 322-324.
連結：
6. Lin, Y. W.; Ho, H. T.; Huang, C. C.; Chang, H. T., Fluorescence detection of single nucleotide polymorphisms using a universal molecular beacon. Nucleic Acids Res. 2008, 36, e123.
連結：

Altmetrics

〈TOP〉

E-mail ：

When an article is available to download, a notice will be sent to your mailbox address.

E-mail ：