Magnetically-Controlled Microfluidic Devices and Structures

这个工程微系统：“XYZ”芯片项目的目标是研究磁性胶体颗粒及其在几种微流体力学应用中的应用。为了有效的药物筛选、化学检测和组合化学，需要小型化和执行平行的化学和生化过程，这激发了人们对微观尺度上化学过程的兴趣。目前大多数技术都依赖于压力驱动和电动过程来运输设备周围的分析物和产品。在这项工作中，在系统中加入了另一个控制参数，即磁场。磁性胶体粒子自组装成链是关键过程。当系在微观流体流动和悬浮分析物表面时。将设计微观流动系统，对表面进行化学图图化，并将磁链连接到表面，然后研究由此产生的流体力学和磁链动力学。要解决的基本问题包括：磁性胶体颗粒链的动力学和机械性能；微观流体力学；磁珠阵列的滤波和筛分能力；并对微磁搅拌器的微尺度搅拌性能进行了研究。举例介绍了涉及细胞或颗粒的筛分或过滤的分离过程，以及在微反应器中有效混合的相反问题。该项目将与斯坦福纳米制造设施合作进行，该设施是NSF国家纳米制造用户网络的一部分。

The goal of this Engineering Microsystems: "XYZ" on a Chip project is to investigate magnetic colloidal particles and their use in several micro-fluid mechanics applications. The need to miniaturize and perform parallel chemical and biochemical processes for efficient drug screening, chemical detection, and combinatorial chemistry motivates interest in chemical processes on a microscopic scale. Most of the current state of the art relies on pressure-driven and electrokinetic processes to transport analytes and products around device. In this work another control parameter, a magnetic field, is added to the system. The self-assembly of magnetic colloidal particles into chains is the key process. When tethered to surfaces in microscopic fluid flow and suspended analytes. The microscopic flow system, chemically patterning the surfaces, and linking the magnetic chains to surfaces will be designed, and then studying the resulting fluid mechanics and magnetic chain dynamics will be investigated. The fundamental issues to be addressed include: the dynamics and mechanical properties of tethered and untethered chains of magnetic colloidal particles; the microscopic fluid mechanics; the filtering and sieving capabilities of magnetic bead arrays; and the micro-scale mixing performance of actuated micromagnetic stirrers. Examples are presented for separation processes involving sieving or filtration of cells or particles, and the converse issue of effective mixing in a microreactor.This project will be conducted in collaboration with the Stanford Nanofabrication Facility, a part of the NSF National Nanofabrication Users Network.