Solventless Sample Preparation Method Using Supercritical or Subcritical Water as the Medium

近十年来，超临界流体萃取作为一种分析样品制备技术受到了广泛的关注。超临界流体萃取的萃取时间较短，大大减少了索氏萃取需要数天的时间和简单的预富集步骤，最重要的是，大大减少了有毒和对环境有害的有机溶剂的用量。然而，在SFE中，一定数量的有机溶剂被用作提取分析物的收集介质和超临界流体的改性剂。另一方面，近年来的研究也表明，固相微萃取（SPME）是一种快速、无溶剂、性能优异的技术。同样，SPME与高效液相色谱（HPLC）耦合用于非挥发性或热不稳定化合物（如农药）的分析也使用少量有机溶剂。由于上述原因，本项目旨在研究开发一种无溶剂样品制备方法，使用超临界或亚临界流体作为萃取介质，其中SPME是主要的萃取技术。结果表明，以超临界流体为介质，SPME - SFE联用可有效地分析水中农药，实现了无溶剂制样工艺。在进一步的开发中，使用超临界水或亚临界水将改进本项目中开发的方法，这是本系列项目的下一个目标。

In the past ten years, supercritical fluid extraction (SFE) is being paid much attention as an analytical sample preparation technique, SFE provides shorter extraction time, which is a great reduction to Soxhlet extraction that may take days to perform, simple preconcentration steps, and most of all, significant reduction in the volumes of toxic and environmentally hazardous organic solvents used. However, in SFE some amounts of organic solvents are used as the collection media for the extracted analytes and as the modifier for the supercritical fluid. On the other hand, recent studies had also shown solid phase microextraction (SPME) to be fast, solvent free and an excellent performance technique. Similarly, SPME coupled to high performance liquid chromatography (HPLC) for non-volatile or thermally unstable compounds such as pesticides analysis also employs a small amount of organic solvent.For these reasons described above, this project has been intended to study the development of a solventless sample preparation method using supercritical or subcritical fluids as the extraction medium where SPME is a major extraction technique. As the results the analysis of pesticides in water has been made effectively by using SPME coupled with SFE with supercritical fluid as the medium and solventless sample preparation process has been realized by this technique. In the further development using supercritical water or subcritical water will improve the method developed in this project and this is the next target of this series of the projects.