以SAM修飾之金奈米粒子應用於免疫分析之研究

SAMs是自我集結單分子層，可以自發性的在不同的金屬基材上形成，其分子藉由化學吸附於基材上，而分子之間靠著凡得瓦爾力集結排列成高度次序、取向性、緊密的單分子層。一般以金奈米粒子為標記物的免疫分析方法中，大部分抗體是以物理性吸附於金奈米粒子上，我們認為有不穩定的問題存在，因此，本篇論文主要是發展一種以SAMs為基礎經由共價結合抗體於金奈米粒子上的技術應用於免疫分析上。首先金奈米粒子在界面活性劑Tween 20的保護下，用16-MHDA和1-UDT以1:100的比例修飾，隨後加入EDC和NHS活化16-MHDA分子末端的羧基，最後半乳糖苷酶抗體以胺基與之鍵結，如此便完成了構築。與物理性吸附抗體的方法做比較，分別實驗於dot-blot、免疫層析試紙以及耐受性的測試，實驗結果發現以SAMs修飾過的金奈米粒子不但較穩定，不會有非專一性蛋白質吸附的問題，而且所使用抗體的量也較少，即可達到相同的偵測極限，減少了分析的成本。

關鍵字

自我集結單分子層；金奈米粒子；抗體

並列摘要

Self-assembled monolayers (SAMs), formed by spontaneous chemisorption of head group of selected organic molecule on suitable materials, represent one major trend in surface chemistry. Van der Waals forces between long alkyl chains orient and stabilize the monolayers. In this paper, we fabricated the covalently-linked bioconjugates of antibody/gold nanoparticles (AuNPs) for immunoassay. The AuNPs were first modified by 16-mercaptohexadecanoic acid (16-MHDA)/1-Undecanethiol (1-UDT) mixture of molar ratio 1:100 under protection of Tween 20. Subsequently, the peripheral carboxylic groups were activated by EDC/NHS as coupling agents. The as-formed NHS-terminated AuNPs covalently combined with the amino groups of anti-β galactosidase antibody and the target bioconjugates were constructed. A comparison of antibody adsorption between chemisorption and physisorption has been done for sensitivity and durability in applying dot-blot and immunochromatography methods. Although covalent immobilization involves more steps technically, antibody covalently bonded on AuNPs are much more stable than antibody immobilized by physisorption. Moreover, SAMs-based method allowed for the more economical use of valuable antibodies.

並列關鍵字

Self-assembled monolayers ； gold nanoparticles ； antibody

參考文獻

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以SAM修飾之金奈米粒子應用於免疫分析之研究

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