碳化金屬有機凝膠於表面輔助雷射脫附游離基質與固相微萃取之應用

Application of Carbonized Metal-Organic Gels as Matrix in Surface Assisted Laser Desorption/Ionization and Solid Phase Microextraction

黃境晟(Jing-Cheng Huang)

指導教授 ： 林嘉和

中原大學/理學院/化學研究所/博士(2019年)

https://doi.org/10.6840/cycu201900301

摘要

本論文以碳化之金屬有機凝膠為主軸，探討碳化後之材料特性並應用於檢測兒茶酚胺。
第一部份：本實驗以金屬源-四氯化鋯 (zirconium tetrachloride, ZrCl4)、配位基-對苯二甲酸 (terephthalic acid, H2BDC)及乙醇-二甲基甲醯胺 (EtOH-DMF)在80 ℃下反應4小時，成功快速製備鋯金屬的金屬有機凝膠 (Zr base metal-organic gels, Zr-MOGs)。由於Zr-MOGs結構的不規則，使結構中具有許多的缺陷位置，而其缺陷位置所接上之官能基 (-OH)可以做為碳化過程中穩定劑的角色，使能簡單、快速且一步製備單一晶相的四方晶型二氧化鋯孔洞性碳材 (tetragonal zirconia nanoporous carbons, t-ZrO2-NPCs)。此外，t-ZrO2-NPCs成功作為基質於表面輔助雷射脫附游離質譜法並檢測兒茶酚胺，偵測極限可達0.49 nM至0.69 nM以及RSD < 9 %，說明此分析方法具有良好的偵測感度與可信度；另外，此分析方法也成功應用在小分子胺基酸以及人類血清上。此外，t-ZrO2-NPCs也成功作為催化劑應用在脂肪酸轉酯化反應，其產率可達95 %以上且經過三次重複催化產率依然可維持在95 %以上，說明t-ZrO2-NPCs材料多樣的應用性與重複利用性。
第二部份：本實驗首次利用碳化含胺基之鋁金屬有機凝膠 (Al-MOG-N)，結合聚甲基丙烯酸酯類高分子 (poly(BMA-EDMA))製備成整體成形萃取管柱 (polymer monolithic microextraction, PMME)，對兒茶酚胺進行固相微萃取 (solid phase microxtraction, SPME)。實驗中比較neat polymer PMME、AlBDC-NH2-polymer PMME、cAlBDC-polymer PMME及cAl-MOG-N polymer PMME四種材料做為PMME吸附劑對兒茶酚胺萃取影響。結果顯示，cAl-MOG-N polymer PMME具有最佳的萃取效果，其原因為cAl-MOG-N具有路易斯酸、羧酸根及雜氮環結構，能有效吸附兒茶酚胺；此外，雜氮環結構會因為碳化溫度不同而有比例上的變化，使吸附與脫附結果不同，導致回收收率上差異。而本實驗以碳化溫度600 ℃為最佳碳化條件，其萃取兒茶酚胺回收率可達95-104 %，萃取管柱之效能R2大於0.996且偵測極限為1.51-1.77 ug/L，column to column與batch to batch之回收率均可達90 %以上且RSD < 5 %。本實驗結果顯示整體成形管柱在SPME技術對兒茶酚胺萃取具有相當潛力。

關鍵字

金屬有機凝膠 ； 表面輔助雷射脫附游離基質 ； 固相微萃取

並列摘要

In this dissertation, porous carbon materials derived from metal-organic gels were developed and characterized. The carbon materials were applied in the determination of catecholamine.
In the first part of this study, Zirconium based metal-organic gel (Zr-MOGs) were synthesized, which composed of zirconium tetrachloride (ZrCl4), terephthalic acid (H2BDC), ethonal (EtOH) and dimethylformamide (DMF) and reacted at 80 ℃ for 4 hours. Due to the disordered structure of Zr-MOGs, such as high hydroxy group (-OH) defect sites, the one-step preparation of tetragonal zirconia nanoporous carbons (t-ZrO2-NPCs) were achieved. In addition, t-ZrO2-NPCs was successfully applied as matrix in surface assisted laser desorption/ionization mass spectrometry (SALDI-MS) determination of catecholamines. The limit of detection limit were in the range of 0.49 nM to 0.69 nM with less than< 9 % relative standard deviations, suggesting the good sensitivity and reproducibility of t-ZrO2-NPCs. It was also applied in the determination of amino acid and catecholamines in human serum. Furthermore, the t-ZrO2-NPCs can also act as catalyst for transesterification of fatty acids with 95% conversion and could be recycle for at least 3 times, suggesting its wide range of application.
For the second part, various nitrogen-doped porous carbon materials derived from aluminum-MOGs (cAl-MOG-N) were developed and embedded in poly (butyl methacrylate-ethylene dimethacrylate) (cAl-MOG polymer) monolithic column in solid phase microextraction of catecholamine. The extraction efficiencies of neat polymer, AlBDC-NH2 polymer PMME, cAl-MOG polymer and cAl-MOG-N polymer PMME were compared. The cAl-MOG-N polymer showed the best extraction efficiency due its Lewis acid, carboxylic acid group and N-doped structure. However, the carbonization temperature affects the ratio of N-doped structure leading to the different loading efficiencies and recoveries for cathecolamine. The optimized condition for carbonization temperature was found to be at 600 ºC, which can achieved 95 to 104 % of extraction recovery. The column efficiency exhibited good linearity (R2 > 0.996), low limits of detection (1.51 to 1.77 ug/L), and high reproducibility based on column-to-column and batch-to-batch efficiencies (> 90 % with RSD < 5 %). These results suggest that the fabrication of monolithic column showed potential for SPME of cathecolamines.

並列關鍵字

Metal organic gel ； Surface assisted laser desorption/ionization ； Solid phase microextraction

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