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|Title: ||Dispersive micro solid-phase extraction for the rapid determination of selected emerging contaminants – method optimization and applications|
|Keywords: ||人造麝香;熱脫附-氣相層析質譜;分散微固相萃取;水分析;二苯甲酮型紫外線防曬劑;Synthetic musks;Thermal desorption–GC–MS;Dispersive micro solid-phase extraction;Water analysis;Benzophenone-type UV absorbers|
|Issue Date: ||2016-06-04 12:21:16 (UTC+8)|
|Abstract: ||一般的萃取方法是耗時、成本較高、對生態不友善，並且有殘留等問題。本論文所提出的分散微固相萃取法 (DmSPE) 結合溶劑脫附或熱脫附技術可改善這些缺點，並且藉由實驗設計進行萃取參數的最佳化。|
本文分為三個部分：在第一個部分，開發及驗證最佳化方法檢測水樣中七個人造麝香的目標待測物。此方法包含DmSPE加上超音波輔助溶劑脫附 (UASD)，並以氣相層析質譜儀 (GC-MS) 進行檢測。水樣中目標待測物的萃取效率及UASD的影響因子是由Box-Behnken design的實驗設計法進行最佳化。最佳萃取條件是在50毫升的水樣中浸入10.1毫克的矽膠基質鍵結十八烷基 (C18) 吸附劑，經過10.4分鐘的劇烈搖盪萃取後，在過濾器上收集及乾燥吸附劑，再以200 μL的正己烷作為脫附溶劑，經過38秒的超音波脫附目標待測物。從城市污水處理廠 (MWTP) 的排放水及河流水樣的初步檢測顯示galaxolide (HHCB) 和tonalide (AHTN) 是兩個最常被檢測到的人造麝香化合物，它們被測到的濃度範圍：污水水樣為88 ~ 690 ng/L，河流水樣為5 ~ 320 ng/L。
在第二部分，是開發一個簡單，快速，無溶劑的檢測方法，將DmSPE結合直接熱脫附 (TD)-GC-MS技術，用於檢測水樣中五個目標麝香待測物。水樣中目標麝香待測物萃取的效率及GC注射埠中熱脫附的條件，其影響的參數以中心合成設計 (CCD) 法進行最佳化，最佳萃取條件包含浸入3.2毫克的C18吸附劑到10毫升的水樣中，劇烈搖盪萃取1.0分鐘之後，在過濾器上收集並乾燥吸附劑。吸附劑再被轉移到一個微試管內，並將其直接插入到GC程式升溫注射器中，而所萃取的目標麝香待測物在337 °C的GC的注射埠中進行熱脫附3.8分鐘。以標準添加法初步進行河流水樣分析，結果顯示HHCB和AHTN的測定濃度範圍為11 ~ 140 ng/L。
最後，我們更進一步以無溶劑法快速檢測水樣中含有OH-官能基的六個二苯甲酮系的紫外光防曬劑，此法包含DmSPE結合同時矽烷衍生及熱脫附 (SSTD)-GC-MS技術。先以Plackett-Burman設計法篩選主要影響因子，選出的主要因子再以CCD作為最佳化探討，而最佳實驗條件包括浸入1.5毫克的Oasis HLB吸附劑到10毫升的水樣中，劇烈搖盪1分鐘後，吸附劑轉移到微試管中，先在122 °C下乾燥3.5分鐘，再加入2 µL BSTFA矽烷化試劑。其中SSTD的程序是將注射埠的溫度保持在70 °C持續2.5分鐘進行衍生化反應，然後溫度迅速增加到340 °C持續5.7分鐘，以利TMS衍生物熱脫附進入GC。以標準添加法初步檢測MWTP的排放水及河流水樣，顯示2-羥基-4-甲氧基二苯甲酮 (BP-3) 是最常被檢測到的二苯甲酮系UV防曬劑，其檢測到的濃度範圍為5.1 ~ 39.7 ng/L。
本論文的結果顯示DmSPE 結合溶劑或熱脫附技術可以滿足檢測的驗證標準，精確檢測水樣中微量的新興汙染物，此技術是簡單，低成本，有效率，對生態友善的檢測方法。在未來，這些方法也可進一步應用在其他領域，例如：食品，飲料，化妝品中新興汙染物的檢測。;The general developed microextraction methods were time-consuming, higher cost, eco-unfriendly, and carryover problems. A dispersive micro solid-phase extraction (DmSPE) coupled solvent/thermal desorption techinque was able to improve these disadvantages, and the parameters were optimized by experimental design, which was proposed by this thesis.
This thesis was divided into three parts: the first part developed and validated an optimized method for the determination of seven synthetic target musks in water samples. The method involves a DmSPE plus ultrasound-assisted solvent desorption (UASD) prior to their determination by gas chromatography-mass spectrometry (GC-MS). Factors affecting the extraction efficiency of the target analytes from water samples and UASD were optimized by a Box-Behnken design (BBD) method. The optimal extraction conditions involved immersing 10.1 mg of a octadecyl (C18) bonded silica adsorbent in a 50 mL water sample. After 10.4 min of extraction by vigorously shaking, the adsorbent was collected and dried on a filter, and the target musks were desorbed by ultrasound for 38 sec with n-hexane (200 μL) as the desorption solvent. A preliminary analysis of the effluents from municipal wastewater treatment plants (MWTP) and river water samples revealed that galaxolide (HHCB) and tonalide (AHTN) were the two most commonly detected synthetic musks; their concentration were determined to range from 88 to 690 ng/L for effluent samples, and 5 to 320 ng/L for river water samples.
In the second part, a simple, rapid, and solvent-free method involves the use of DmSPE coupled with direct thermal desorption (TD) -GC-MS for the analysis of ﬁve target musks in water samples. The parameters affecting the extraction efﬁciency of the target analytes from water sample and the thermal desorption conditions in the GC injection-port were optimized using a central composite design (CCD) method. The optimal extraction conditions involved immersing 3.2 mg of a C18 adsorbent in a 10 mL water sample. After extraction by vigorously shaking for 1.0 min, the adsorbents were collected and dried on a ﬁlter. The adsorbents were transferred to a micro-vial, which was directly inserted into GC temperature programmed injector, and the extracted target analytes were then thermally desorbed in the GC injection port at 337 °C for 3.8 min. Using a standard addition method, a preliminary analysis of the river water samples revealed that the concentrations of HHCB and AHTN were determined to in the range from 11 to 140 ng/L.
Finally, a solvent-free method involves the use of DmSPE followed by the simultaneous silylation and thermal desorption (SSTD) -GC-MS for the rapid analysis of six benzophenone-type UV absorbers in water samples. A Plackett-Burman design was used for screening and a CCD for optimizing the major factors was applied. The optimal experimental conditions involved immersing 1.5 mg of the Oasis HLB adsorbent in a 10 mL portion of water sample. After vigorous shaking for 1 min, the adsorbents were transferred to a micro-vial, and were dried at 122 °C for 3.5 min, after cooling, 2 μL of the BSTFA silylating reagent was added. For SSTD, the injection-port temperature was held at 70 °C for 2.5 min for derivatization, and the temperature was then rapidly increased to 340 °C to allow the thermal desorption of the TMS-derivatives into the GC for 5.7 min. Using a standard addition method, a preliminary analysis of the MWTP efﬂuent and river water samples revealed that 2-hydroxy-4-methoxybenzophenone (BP-3) was the most common benzophenone-type UV absorber present. The concentrations of BP-3 ranged from 5.1 to 39.7 ng/L.
The preliminary results of this dissertation reveals that these methods can satisfy analytical validation criteria, allow precise measurement of the trace levels of emerging contaminants in aqueous samples, and they are simple, low cost, effective, and eco-friendly method. In the future, these methods also can be further studied to apply in other fields, e.g., food, beverage, pharmaceutical, cosmetic, etc.
|Appears in Collections:||[化學研究所] 博碩士論文|
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