| 摘要: | Mirex是個高度氯化的耐燃劑，在1960年代中期開始被拿來當作農藥，然後也被添加於塑膠、橡膠、塗料、電器產品中做為耐燃劑。因為毒性的關係使得這種化學物質在1970年代被禁止，而由其它像是Dechlorane 602 (簡稱Dec 602)、Dechlorane 603 (簡稱Dec 603)、Dechlorane 604 (簡稱Dec 604)這些高度氯化的化合物所取代，特別是耐燃特性與Mirex相似的Dechlorane Plus (簡稱DP)。
以超音波輔助分散式液液微萃取法(UA-DLLME)搭配氣相層析-電子捕捉負離子質譜儀(GC-ECNI-MS)開發出一個簡單，且有機溶劑用量少的方法，以檢測水樣中的五個氯化耐燃劑為本研究的主要目標。將影響來自水樣中待測物萃取效率的參數進行了有系統的研究。最佳化條件為將1 mL乙?(作為分散劑)以及60 μL四氯化碳(做為萃取劑)的混合液快速注入於10 mL含有0.5克氯化鈉的水樣中。經過1分鐘的超音波震盪後，以6000 rpm的速率(大約3940 g)離心10分鐘。取出沉澱相並且吹乾，接著以50 μL的內標準品回溶就可以進行之後的GC-ECNI-MS分析。偵測極限為0.05-0.5 ng/L。對其做精密度及準確度的測試，其相對標準偏差(RSDs)皆小於10 %，在不同的水樣中測得的總濃度範圍是從0.15至0.33 ng/L。
整體來說，超音波輔助分散式液液微萃取是一個很好的替代萃取方法，用來測定環境水樣中的氯化耐燃劑，因為它是一個簡單、花費低、快速、且對環境友善的分析方法。
Mirex was a highly chlorinated flame retardant. During the mid-1960s, it was used as a pesticide and also as a flame retardant in plastics, rubber, paint, and electrical goods. The nonagricultural uses of this chemical were banned in the 1970s because of its toxicity, and then partially replaced by other highly chlorinated compounds, such as Dechlorane 602, Dechlorane 603, Dechlorane 604 and, in particular, Dechlorane Plus, which have flame-retardant properties similar to that of mirex.
A simple and solvent-minimized procedure for the determination of five chlorinated flame retardant in aqueous samples using ultrasound-assisted dispersive liquid-iquid microextraction (UA-DLLME) coupled with gas chromatography–electron-capture negative ion mass spectrometry (GC-ECNI-MS) is presented. The parameters affecting the extraction efficiency of analytes from water samples were systematically investigated. The best extraction conditions involved the rapid injection of a mixture of 1.0 mL of acetonitrile (as a dispersant) and 60 μL of carbon tetrachloride (as an extractant) into 10 mL of water containing 0.5 g of sodium chloride in a conical bottom glass tube. After ultrasonication for 1.0 min and centrifugation for 10 min at 6,000 rpm(ca. 3940 g). The sedimented phase was evaporated to dryness and re-dissolved in 50 μL of acetone containing internal standard for further GC-ECNI-MS analysis. The limits of detection were 0.05-0.5 ng/L. The precision for these analytes, as indicated by relative standard deviations (RSDs), was less than 10% for both intra- and inter-day analysis. Their total concentrations were determined in the range from 0.15 to 0.33 ng/L in various water samples.
Overall, UA-DLLME appears to be a good alternative extraction method for the determination of chlorinated flame retardants in environmental water samples, in that it is a simple, low cost, rapid, and eco-friendly analytical method. |
