多色螢光金奈米團簇合成、改質和生物分子接枝

Synthesis, Modification and Bio-conjugaion of Multicolor Fluorescent Gold Nanoclusters

謝鈞泰(CHUN-TAI HSIEH)

指導教授 ： 張恒雄

中原大學/工學院/生物醫學工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000759

摘要

摘 要
二氧化矽材料已普遍用於奈米材料包覆，包括半導體量子點、奈米金、奈米銀、氧化鐵等材料，除不影響內部奈米材料物理特性，亦提高其生物相容性。本研究室發現金奈米粒子小於2奈米之後，利用特定硫醇基分子或枝狀高分子表面修飾後可放出不同顏色螢光，但目前螢光金奈米團簇的生物相容性、光學物理特性和環境與光學穩定性都還有改善的空間。
本研究主要對於多色螢光金奈米團簇製程技術進行發展，並將其進行改質與生物接枝，最後以生物標定來證實其應用性。首先對不同之金奈米團簇進行熱處理來增強量子產率，再以胎牛血清 ( bovine serum albumin，BSA ) 於不需反應試劑之情況下進行非特異性鍵結；並使用界面活性劑 (Didodecyldimethy-
lammonium bromide ，DDAB) 將親水性金團簇改質成疏水性，以Stober method將四乙基矽氧烷（Tetraethyl orthosilicate，TEOS）進行二氧化矽包覆試驗，提高抗光漂白能力。最後，將二氧化矽表面官能化胺基，並藉由胺基和細胞膜標定分子BAM (Biocompatible Anchor for cell Membrane ) 去進行生物接枝反應，並利用BAM成功標定至間葉幹細胞之細胞膜表面，達到生物醫學上之應用。

關鍵字

多色螢光金奈米團簇 ； 生物接枝 ； 官能化 ； 四乙基矽氧烷

並列摘要

Abstract
The silica coating has been widely used in surface modification of nanomaterials including semiconductor quantum dot, gold nanoparticles, silver nanoparticles and iron oxides. We have found that gold nanoparticles with size smaller than 2 nm could enhance its fluorescent properties via surface-protected molecules such as the specific alkanethiolate or branch polymers. But it is still challenged on its biocompatibility, physics characterization, physiological and optic stability to improve at present.
This study investigated the bioconjugation of multicolor fluorescenct gold nanoclusters and its application in bio-labeling. First, we found the enhanced quantum Yield of different gold nanoclusters via thermal treatment. Next, bovine serum albumin (BSA) molecules could proceed nonspecific binding without croslinker. We found that the didodecyldimethy-lammonium bromide (DDAB) surfactant is a good agent for gold nanoclusters transferring from hydrophilic to hydrophobic solvent. Silica-coating of fluorescent gold nanoclusters can enhance the ability of antiphotobleaching. Finally, fluorescent gold nanoclusters tagged with membrane marker successfully labeled the cell membrane of mesenchymal stem cells.

並列關鍵字

bovine serum albumin ； bio-labeling ； gold nanoclusters ； bio-conjugation

參考文獻

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