導引磁性粒子之虛擬通道網路

Abstract

近年來生醫科技朝向儀器微小化、快速分析、大量樣本檢測的目標發展。透過微機電系統技術，可以將傳統生醫檢測設備的功能整合於一片釐米大小的晶片上，進行生物分析如混合、操作、傳輸、分離等功能。在生醫領域中，這類晶片被稱為微流道晶片。 微流道晶片因具有「實體」的通道，將無可避免地造成流道的阻塞和汙染，導致晶片壽命減少。為了解決此問題，有科學家運用了介電泳動(Dielectrophoresis)原理建構「虛擬」通道，雖然沒有阻塞和汙染的問題，但漏電問題在充滿液體的操作環境中是一大隱憂。 為了解決實體通道和介電泳虛擬通道的缺點，本研究提出了以磁建構之虛擬通道。將會用理論闡述在外加磁場的影響下，被磁化的鎳金屬結構如何地影響磁性粒子在虛擬通道中流動；最後會呈現虛擬通道導引磁性粒子的效果，分別是擴大端口收集範圍的漏斗型流道、進行轉彎角度測試的轉彎流道、將不同功能流道進行連結的動態分流結構以及改變粒子導引方向的動態旁引結構。

Recently, biomedical technology tends to achieve the goal of miniaturization of instruments, high-speed analysis and mass operation. The micro-electro-mechanical systems (MEMS) technology allows us to integrate the functions of a conventional biomedical analysis instrument into a centimeter-sized chip, which can be used for mixing, manipulation, transport and separation, etc. In the field of biomedical science, such a chip is called microfluidic chip. Owing to “substantial” channels of microfluidic chip, clogging and contamination are inevitable. The chip has a limited lifetime. To solve this problem, some researcher has proposed a “virtual” channel by using the theory of dielectrophoresis (DEP). Despite of no clogging and contamination, leakage current has a chance to cause safety problem when operating. In this study, we propose a novel virtual channel by the theory of magnetism in order to solve the drawbacks of both substantial channels and virtual channels by DEP. This work illustrates how the magnetized nickel structure affects magnetic beads on the condition of utilizing an external magnetic field. Furthermore, we also demonstrate the results of guiding magnetic beads in virtual channel. Collecting more magnetic beads via funneled channel, testing the angle of turning channel, connecting two functional channels through shunting structure and changing the direction of bead movement via branching structure.