奈米金-石墨烯複合基材修飾聚多巴胺應用於表面增強拉曼散射技術檢測核鹼基之方法開發

Polydopamine Modified Gold/graphene/aluminum Hybrid Nanocomposites as SERS Active Substrates for the Detection of Nucleobases

卜玉欣(Yu-Hsin Pu)

指導教授 ： 黃俊嬴

高雄醫學大學/生命科學院/醫藥暨應用化學系碩士班/碩士(2020年)

摘要

本研究在奈米金-石墨烯複合基材表面修飾多巴胺之高分子層作為辨識相，並結合表面增強拉曼散射技術檢測水溶液中的核鹼基。透過將奈米金-石墨烯複合基材浸泡於鹼性的多巴胺溶液中，多巴胺會自發性聚合並修飾在複合基材表面，修飾層厚度可經由控制浸泡多巴胺溶液的時間或濃度進行調整，並且預期聚多巴胺具苯環、羥基及胺基的結構和核鹼基之間可產生不同強弱程度的交互作用進而提升複合基材檢測核鹼基的選擇性並達到選擇性感測之效果。
研究結果顯示，聚多巴胺可成功修飾於奈米金-石墨烯複合基材表面並維持優異的水穩定性，而由多巴胺聚合時間多寡調節之修飾層厚度也影響核鹼基的表面增強拉曼散射訊號。實驗結果也顯示聚多巴胺的修飾確實顯著提升在酸性的環境下檢測核鹼基中的腺嘌呤之選擇性，其偵測極限約為0.25 μM。基於成功改善複合基材檢測核鹼基的選擇性及靈敏度，本研究所提出修飾聚多巴胺的表面增強拉曼散射基材確實具有潛力可應用於相關疾病的初步臨床診斷。

關鍵字

表面增強拉曼散射技術

並列摘要

In this study, poly-dopamine (PDA) film is modified on the gold/graphene/aluminum hybrid nanocomposites to increase the selectivity for the detection of nucleobases in aqueous solutions by surface-enhanced Raman scattering (SERS) technique. The PDA can be spontaneously modified on hybrid nanocomposites by immersing nanocomposites with dopamine solutions under alkaline condition. Besides, the thickness of poly-dopamine film can be controlled by varying immersing time or the concentration of dopamine. In addition, it’s expected that PDA would have significant interactions with nucleobases through aromatic groups, hydroxyl groups and amino groups, which can increase selectivity for detecting the target analytes.

Results indicated that PDA can be modified on the surface of gold/graphene/aluminum hybrid nanocomposites with high stability and the thickness of PDA is related to the SERS signals of detected nucleobases. The results also showed that the presence of PDA did increase the selectivity for the detection of adenine under acidic condition with a sensibility of 0.25 μΜ. Based on the successfully improvement the selectivity and sensitivity of detecting nucleobases, the PDA coated SERS nanocomposites can be applied for preliminary clinic diagnosis of related diseases, which is under studying.

並列關鍵字

SERS

參考文獻

(1) Denessiouk, K. A.; Rantanen, V. V.; Johnson, M. S. Adenine Recognition: A Motif Present in ATP-, CoA-, NAD-, NADP-, and FAD-Dependent Proteins. Proteins Struct. Funct. Genet. 2001, 44(3), 282-291.

(2) Smelt, M. J.; Faas, M. M.; de Haan, B. J.; de Vos, P. Pancreatic Beta-Cell Purification by Altering FAD and NAD(P)H Metabolism. Exp. Diabetes Res. 2008, 165360.

(3) Alula, M. T.; Yang, J. Photochemical Decoration of Silver Nanoparticles on Magnetic Microspheres as Substrates for the Detection of Adenine by Surface-Enhanced Raman Scattering. Anal. Chim. Acta 2014, 812, 114–120.

(4) Thangaraj, R.; Nellaiappan, S.; Sudhakaran, R.; Kumar, A. S. A Flow Injection Analysis Coupled Dual Electrochemical Detector for Selective and Simultaneous Detection of Guanine and Adenine. Electrochim. Acta 2014, 123, 485–493.

(5) Yang, F. Q.; Guan, J.; Li, S. P. Fast Simultaneous Determination of 14 Nucleosides and Nucleobases in Cultured Cordyceps Using Ultra-Performance Liquid Chromatography. Talanta 2007, 73 (2), 269–273.