β-環糊精增強次氯酸氧化Luminol之化學發光及應用

Enhancement in Chemiluminescence by β-Cyclodextrin for the Oxidation of Luminol by Hypochlorite and Its Applications

陳育錚(Yu-Cheng Chen)

指導教授 ： 林萬寅

國立臺灣大學/理學院/化學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00790

摘要

本研究使用自行組裝的流動注入分析系統探討β-cyclodextrin (β-CD) 增強次氯酸氧化Luminol的化學發光的機制。研究的結果發現：當5 mM的β-CD添加至此化學發光的系統並且維持在pH = 9.5的狀態時，化學發光的強度可增強約20倍。推測此化學發光增強的機制可能是因為產生β-CD的包絡物以穩定化學發光的中間態。在研究中同時對pH值、流速、反應物 (luminol、β-CD、次氯酸) 的濃度與混合的型式等因素對於化學發光的強度之影響做詳細的探討與最佳化。此化學發光系統可同時應用檢測抗氧化劑，如；curcumin、hydroquinone等。因抗氧化劑會破壞化學發光所產生的自由基，而造成化學發光的效率降低，其線性動態範圍與不同的抗氧化劑的抗氧化能力有關。使用化學發光的方法對於沒有發色團 (chromophoric) 官能基的化合物特別有用，對於大部分胺基酸可測定的濃度值可達0.1~1 mM。此外，半胱胺酸 (cysteine) 與甲硫胺酸 (methionine) 在沒有其他顯著干擾胺基酸的影響下可量測濃度值為1~10 μM。而對於缺乏選擇性的缺點可在進行化學發光偵測前先流經色層分析儀。

關鍵字

次氯酸 ； β-環糊精 ； 化學發光

並列摘要

We have studied the enhancement in chemiluminescence (CL) for the oxidation of luminol with hypochlorite caused by β-cyclodextrin (β-CD) using a home-made flow injection analysis system. A 20-fold increase in CL intensity was observed upon addition of 5 mM β-CD to the CL system at pH 9.5. The CL-enhancement may result from the increases in the overall CL efficiency and the fluorescence quantum yield from the stabilization of the CL intermediate(s) and/or product in the interior of the inclusion complex with β-CD. The effects of pH, flow rate, concentrations of reagents (luminol, β-CD, hypochlorite), and modes of reagent mixing on CL emission were also investigated and optimized. The CL system has been applied to the determination of antioxidants such as curcumin, hydroquinone etc. The antioxidants destroy the radicals involved in the CL reaction, causing a decrease in CL emission. The linear dynamic ranges vary for different antioxidants with different antioxidative power. The CL method is useful for the detection of compounds that have no chromophoric groups. Inhibition of CL emission allows the determined of most amino acids at 0.1-1 mM. On the other hand, cysteine and methionine can be determined over the concentrations of 1-10 μM without significant interferences from other amino acids. The lack of selectivity requires a chromatographic column prior to the CL detection.

並列關鍵字

chemiluminescence ； luminol ； β-cyclodextrin ； hypochlorite

參考文獻

(18)Dapkevicius, A.; van Beek, T. A.; Niederlander, H. A. G.; de Groot, A. Analytical Chemistry 1999, 71, 736-740.

(11)Spence, D. M.; Crouch, S. R. Analytical Chemistry 1997, 69, 165-169.

(21)Krstulovic, A. M. Chiral Separations by HPLC: New York, 1989.

(26)Lough, W. J. Chiral Liquid Chromatography: USA, 1989.

(28)Seitz, W. R. Journal of Physical Chemistry 1975, 79, 101.