近來，文獻研究發現，加入少量的奈米金粒子，可以大幅的提昇傳統溫度循環式的
PCR(Polymerase Chain Reaction)反應器的效率 Li et al. [1]。雖然，提昇這個效應的機制尚未釐清，但是一般認為，加入奈米金粒子可以增加系統的熱傳效率 Li et al. [２]。而本實驗的主要研究方向為，奈米金粒子加入 Rayleigh-Bénard 對流的反應槽 (RBCC)內，同時執行 PCR， 然後研究奈米金粒子的流動特性，並且其中有何影響讓熱趨使流動更加旺盛。然後由電泳實驗分析中觀察到，在 RBCC中加入奈米金粒子，亦可以提昇 PCR效率。並找到一個最理想的奈米金粒子濃度提昇 PCR效率，這點與先前發表的文獻有著相似的結果。又由量測 RBCC內的流動速度分析中，可以顯現出，加入奈米金粒子，
同時也改變了流場的型態。所以論文中將詳細地討論，流場和 PCR效率之間兩者相互關係的機制。

Recently, it is shown that the addition of small amount of gold nano-particles can drastically enhance the efficiency of a traditional temperature cycling polymerase chain reaction (PCR) machine in the amplification of DNA, Li et al. [1]. Although the enhancement mechanism remains unknown, it is generally believed that the heat transfer efficiency of the system is increased by the addition of the nanoparticles, Li et al. [2]. A Rayleigh-B´enard convection cell (RBCC) is setup to study the heat driven flow properties of nano-particle enriched fluids and to perform the PCR at the same time. In electrophoresis experiments, it is found that the addition of gold nano-particles also enhances the efficiency of the PCR in a RBCC. Similar to previous findings, there is an optimal nano-particle concentration for the PCR.Velocity measurements reveal that the convection flow pattern in the RBCC is changed by the addition of nano-particles in the fluids. Possible mechanisms for the relation between the flow patterns and the PCR efficiency are discussed.

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