在最近十年，微機電技術比傳統技術來的越來越有效率。介電泳是一種以電性操作微米顆粒且容易與其他檢測技術相結合的方法。自一九五一年起，介電泳現象定義為極化粒子在高電場下移動的情形，此外，負介電泳最適合用來捕捉溶液中的微粒，與介電泳相比，液體介電泳可視為介電泳中的特例，液體介電泳為液體朝非均勻電場區域中較高電場流動的現象，其中也討論了介電泳現象與液體介電泳現象的實驗與理論。本研究利用液體介電泳方式，建立二十奈升的去離子水液珠，其中液珠包含已經定位好的十微米以及十五微米的塑膠顆粒。本研究亦完成了一個在平行板電極上同時應用介電泳與液體介電泳的方法。

In recent ten years, Micro-Electro-Mechanical Systems (MEMS) technology is established and is more efficient rather than the conventional ones. dielectrophoresis (DEP) is one of the electrical methods to manipulate μ-particles, and can be easily combined with subsequent analyses based on electric fields. In 1951, DEP was first defined as polarizable particles moving into regions of higher electric field intensity. Besides, negative DEP is practicable in trapping particles suspended in the liquid. In contrast to DEP, liquid DEP (LDEP) is a particular case of DEP. The phenomenology of liquid DEP is that the dielectric liquid tends to flow towards to the regions of high electric field intensity under a non-uniform electric field. Additionally, the relationship between DEP and LDEP is discussed experimentally and theoretically. Furthermore, this research presents a method to create a 20 nl droplet of deionized water by LDEP. Finally, the creation of a water droplet containing 10 μm and 15 μm polystyrene beads at the desired location from the continuous flow driven by LDEP is successfully demonstrated using the developed method. This work presents a practical method of DEP and LDEP based on parallel electrodes for single particle trapping application.

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