使用固相微萃取技術進行空氣中三氯氨被動式採樣之方法開發

Abstract

三氯氨有可能來自氯與有機氮的反應，例如在游泳池中，游泳者會貢獻不同種類的有機氮，包括：汗水、尿液、或皮膚微粒，並可能進一步與氯反應而成為三氯氨；而過去的研究發現暴露於三氯氨可能會造成孩童或者成人的急性以及慢性健康效應。為了監測空氣中三氯氨濃度，現有的方法使用採樣幫浦；然而需要複雜的樣本前處理與分析流程。另一方面，固相微萃取技術則結合採樣、前濃縮、與直接注入樣本進入基本氣相萃取系統等特性，展現許多優於傳統方法之優點。因此，本研究的目的為開發空氣中三氯氨的固相微萃取被動式採樣方法。 本研究首先以氯化氨(或硫化氨)與次氯酸鈉在酸性緩衝液中反應形成三氯氨之溶液，進而將三氯氨溶液注入空氣採樣袋並將之汽化，以獲得已知濃度之氣狀三氯氨。為了評估擴散式固相微萃取採樣器，本研究經測試不同固相微萃取纖維後發現，Carboxen/DVB最適合本研究之所需。 本研究將環己烯先吸附至所選用的纖維上後，接著將纖維插入空氣採樣袋以進行三氯氨之暴露測試；而所生成之衍生物(一氯環己烷)則使用氣相層析/質譜儀分析。本研究所測試的衍生物於0.01ng至1ng之間具有良好線性，而方法偵測極限為0.003ng。 本研究使用氣袋進行靜態暴露測試，而所得之實驗採樣率為1.75×10-7±5.7×10-8 cm3/se。然而，未來應持續驗證，以確認採集效果是否具有重覆性；此外，亦應探討各種環境因素的可能影響。

Trichloramine might possibly be formed when organic nitrogen sources, such as creatinine, arginine, histidine, or urea, react with chlorine. In swimming pools, visitors can contribute various kinds of organic nitrogen, such as sweat, urine, or skin particles, which would further react with chlorine to form trichloramine. Trichloramine has been observed that the exposures might cause acute and chronic health effects in both children and adults. To monitor the concentrations of trichloramine in air, current available method employed sampling pump and required complicated sample preparation and analysis procedures which makes it uneasy to assess the exposures. On the other hand, solid phase microextraciton (SPME) presents many advantages over conventional analytical methods by combining sampling, preconcentration, and direct transfer of the analytes into a standard gas chromatograph (GC) system. Therefore, the purpose of this study was to develop a convenient sampling method, i.e., diffusive sampling, for trichloramine by SPME. Trichloramine in solution was first prepared by mixing ammonium sulphate or ammonium chloride with sodium hypochlorite in acidic phosphate buffer. Known concentrations of gaseous trichloramine were then generated in Tedlar air bags through the injections of trichloramine solutions followed by vaporizations. To quantify the derivative, a range of derivative between 0.01ng to 1ng defined in this research showed good linearity with method detection limit 0.003ng. For the validations of the SPME diffusive sampler, Carboxen/DVB fiber was chosen, and cyclohexene was first loaded onto the fiber. After the exposure of trichloramine, the derivative formed o-fiber, i.e., chlorocyclohexane, was quantified by GC/MS. By using the airbags as the static exposure system, the sampling rate of the SPME diffusive sampler for trichloramine was estimated to be 1.75×10-7±5.7×10-8 cm3/sec. However, further experiments are still needed to confirm the repeatability of the findings, and also to validate the effects of environmental factors on the performance of the sampler.