利用1,1-二氯乙烯功能化固相萃取晶片建立感應耦合電漿質譜儀連線分析系統進行天然水樣中微量元素分析之研究

Development of 1,1-Dichloroethene-Functionalized Solid-Phase Extraction Chip Combined with Inductively Coupled Plasma Mass Spectrometry for Online Determination of Trace Elements in Natural Waters

陳順娘(Shun-Niang Chen)

指導教授 ： 孫毓璋

國立清華大學/原子科學院/生醫工程與環境科學系/碩士(2013年)

摘要

感應耦合電漿質譜儀 (Inductively coupled plasma-mass spectrometry, ICP-MS) 係目前最強而有力測定微量元素的工具，但是在面對具有複雜基質的樣品時，常會因為嚴重的基質干擾效應，導致分析結果出現嚴重的偏差問題。為了有效解決此問題，在利用感應耦合電漿質譜儀進行複雜樣品中微量元素分析時，常需搭配一套樣品前處理技術使用，才能有效降低基質干擾問題，甚至達到前濃縮的效果，及提升分析結果的可信度。
近年來，許多化學反應裝置趨向微小化，固相萃取亦集積化於一微小基板上，因為具備如試劑/樣品使用量少、反應時間短以及分析系統的縮小等獨特的優點，使晶片型固相萃取受到相當地關注。
在本研究中，以功能化聚甲基丙烯酸甲酯 (Poly (methyl methacrylate)，簡稱PMMA，英文Acrylic) 流控晶片當作固相萃取吸附材，並搭配感應耦合電漿質譜儀進行微量元素的線上分析。值得注意的是，此固相萃取晶片流道表面經過強鹼水解 (Hydrolysis)，丙烯醯胺 (Acrylamide) 乙烯化 (Vinylized) 與塗佈上1,1-二氯乙烯 (1,1-dichloroethene) 等處理，藉由流道表面的氯與待分析的微量元素作用，達到濃縮分離的目的；接著再利用0.5% (v/v) 硝酸將吸附於流道表面的分析物沖提下來，導入感應耦合電漿質譜儀進行測定。所建立的連線分析系統在最佳化參數探討後，以NIST出品的標準參考物質1643e含鹽水樣，來進行方法確效。根據實驗結果，使用本研究開發的方法不僅可以減少試劑與樣品的使用量，同時透過自動化閥向的設計，使整體系統簡單易操作，各個元素在樣品體積50 μL下的偵測極限也可低達0.003–0.021 μg L–1。在透過一系列的實驗驗證可知，本研究所提出的技術確實可實際應用在天然水樣中的微量元素分析，相較於過去傳統填充螯合樹脂的固相萃取管柱，功能化的聚甲基丙烯酸甲酯微流控晶片不僅萃取效率佳，且晶片製作上更加便宜。

關鍵字

晶片型固相萃取 ； 感應耦合電漿質譜儀 ； 功能化聚甲基丙烯酸甲酯

並列摘要

The effectiveness of inductively coupled plasma-mass spectrometry (ICP-MS) for detecting trace elements has been demonstrated. Despite the superior detection features of ICP-MS in trace element analysis, sample pretreatment is still required to avoid unpredictable suppression or enhancement effects due to the presence of the concomitant matrices. To conquer the obstacles in using ICP-MS as a tool in trace analysis, which involves an efficient pretreatment and a sensitive detection, coupling the ICP-MS with a proper online sample processing technique is considered as an indispensable prerequisite.
Recent advances in the miniaturization of many chemical reactors have facilitated the integration of solid-phase extraction (SPE) in minute substrates. Up to date, on-chip SPE techniques have attracted considerable attention because unique advantages, such as low reagent/sample requirement, short reaction time, and so on, benefit from downsizing the dimensions of analytical systems.
In this study, we employed a functionalized poly (methyl methacrylate) (PMMA) chip as a SPE adsorbent, and then combined with ICP-MS for online determination of trace elements. Notably, the channel surface of the functionalized PMMA chip was hydrolyzed by sodium hydroxide, vinylized by acrylamide, and then coated with 1,1-dichloroethene. The hyphenated system was optimized, and then, the analytical reliability of this system was confirmed by using it to analyze the certified reference materials—NIST 1643e (artificial saline water). Based on obtained results, the dramatically reduced consumption of chemicals and “hands-on” manipulations enabled the realization of a simplified and relatively clean procedure with extremely low detection limits (σ= 3, n= 7) over the range 0.003–0.021 μg L–1 for detecting Mn, Co, Ni, Cu, Cd, and Pb in 50-μL samples. A series of validation experiments indeed indicated that our proposed technique appeared uniquely suited for determining levels of trace elements in natural water samples. In comparison with conventional SPE column packed with chelating resins for the determination of trace elements, the functionalized PMMA fluidic chip was not only efficient but also more cost-effective.

並列關鍵字

Chip-based solid-phase extraction ； Inductively coupled plasma-mass spectrometry (ICP-MS) ； Functionalized PMMA

參考文獻

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