離子液體修飾電極的製備與分析應用

Preparation and Electroanalytical Applications of Ionic Liquid-Modified Electrodes

江姿岑(Tzu-Tsen Jiang)

指導教授 ： 鄭淑華

國立暨南國際大學/科技學院/應用化學系/碩士(2013年)

https://doi.org/10.6837/NCNU.2013.00197

摘要

本研究合成帶有胺基之離子液體1-propylamine-3-methylimidazolium bromide (NH2-IL)，再利用電化學定電位氧化的方式，使NH2-IL之NH2端因氧化產生自由基，以共價鍵結嫁接至網版印刷碳電極(SPCE)上，完成電極的修飾。並透過scanning electron microscope (SEM)、electron spectroscopy for chemical analysis (ESCA)、contact angle以及electrochemical impedance spectroscopy (EIS)的鑑定與分析，以證明NH2-IL嫁接於SPCE電極表面。
所製備之SPCE-NH-IL修飾電極，利用循環伏安法在不同pH值的緩衝溶液環境中偵測dopmaine、ascorbic acid以及uric acid。由於離子液體具有良好的導電性質，可以幫助電子傳遞以提升dopamine、ascorbic acid以及uric acid的偵測效果；更進一步在溶液中添加界面活性劑(CTAB)，使得電極表面所帶有的正電荷數目增加，便能在dopamine與ascorbic acid的混合溶液中排除ascorbic acid的偵測干擾。使用循環伏安法偵測不同濃度的dopamine及ascorbic acid，其線性範圍為60 μM ~ 2 mM、100 μM ~ 2 mM；偵測極限為6.14 μM和1.10 μM。若改用差式脈波伏安法行定量分析，dopamine的線性範圍為5 μM ~ 60 μM、偵測極限可達0.171 μM；而ascorbic acid的線性範圍為5 μM ~ 60 μM、偵測極限可達0.186 μM。

關鍵字

離子液體 ； 多巴胺 ； 界面活性劑 ； 差式脈波伏安法

並列摘要

In this study, 1-propylamine-3-methylimidazolium bromide (NH2-IL) was been synthesized and electro-grafted on a screen-print carbon electrode (SPCE-NH-IL). The surface characteristic of modified electrode was investigated by scanning electron microscope (SEM), electron spectroscopy for chemical analysis (ESCA), water contact angle technique, and electrochemical impedance spectroscopy (EIS) analysis system.
SPCE-NH-IL was employed for the determination of dopamine (DA), ascorbic acid (AA) and uric acid (UA). Cyclic voltammetry studies shows that SPCE-NH-IL slightly improved the electrochemical behavior of DA, AA and UA compare to bare SPCE. The oxidation potential of DA, AA and UA were 0.35 V, 0.30 V and 0.43 V, respectively. The larger peak separation between DA and AA can be achieved when surfactane (CTAB) was added into sample solution.
Using different pulse voltammetry (DPV) method, a selective and simultaneous determination of DA and AA has been explored at the modified electrode. The calibration curves were linear in the 5 μM to 60 μM for dopamine and ascorbic acid, the detection of limit is 0.171 μM and 0.186 μM .

並列關鍵字

Ionic liquid ； grafting ； dopamine ； surfactant ； DPV

參考文獻

第六章 參考文獻

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