核殼粒子因其在許多領域廣泛應用而受到關注，例如生物醫學應用、催化、電子學、光子晶體、藥物遞送、組織工程等。殼的合成方法有很多，例如化學合成、化學氣相沉積、自組裝、膠體聚集、膜沉積和生長等。據文獻指出，相較於批次反應，以微流體製備核殼粒子具有控制其結構和性能的優點，並且能簡化步驟。而目前使用微流體技術製備核殼粒子大多是利用磁力、慣性力或是液滴微流體，利用磁力、流體力學或液滴的方式往往需要對粒子本身進行一些前處理或是針對不同的粒子需要不同的流道設計，而這些前處理可能會破壞某些粒子特性，若通入粒子為細胞，這些處理可能會毀損細胞，因此我們利用單邊指叉狀(interdigital transducer, IDT)電極在壓電材料上產生表面聲波(surface acoustic wave , SAW)的方式，讓聲波傳遞至流道內並且推動粒子橫跨多層流道，粒子藉此在不同溶液中反應，利用聲波的特性就不須對於粒子或細胞進行預先標記或是表面處理，也不會對微粒子有任何的汙染，這樣的方法幾乎適用於所有微粒子。
本研究旨在探討如何利用聲波微流體晶片使粒子在單一流道內進行橫向移動，並嘗試在PS粒子表面進行反應生長出一層金殼，以及找出最適合的操作參數。結果顯示，利用微流體晶片製備的PS-Au核殼微粒表面比批次製備的更為光滑平順，微粒之間的均勻性佳，並且可以妥善保存於正十二烷中。

In this study, surface acoustic wave microchips were used to move particles laterally through different streams such that a layer of gold were formed on the surface of polystyrene particles. The results showed that, using single-phase-flow approach, formation of the gold on the particle surface was sporadic and not uniform. This could be due to depletion of the reaction agents on the surface of particles. On the contrary, the two-phase-flow approach (i.e. liquid-oil), allows formation of the gold shell on the particles to be smooth and uniform. Also, increasing the concentration of reducing agent decrease the reaction time.

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