Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Integrated microfluidic isolation platform for magnetic particle manipulation in biological systems

Published

Author(s)

Elizabeth Mirowski, John M. Moreland, Stephen E. Russek, Michael J. Donahue

Abstract

We have developed a micromachined fluid-cell platform that consists of patterned magnetic thin-film elements supported on a thin silicon-nitride membrane. In the presence of an external magnetic field, the field gradients near the magnetic elements are sufficiently large to trap magnetic particles that are separated from the patterned films by a 200 nm thick nitride membrane. The two main applications of this fluid-cell platform are to provide a means to control and position magnetic microparticles, based on their size and magnetic susceptibility. We determine the characteristic trapping forces of each trap in the array by measuring the Brownian motion of the microparticle as a function of applied external field. Typical force constants and forces on the superparamagnetic particles are 4.8 x 10-4 {plus or minus} 0.7 x 10-4 N/m and 97 {plus or minus} 15 pN respectively.
Citation
Applied Physics Letters
Volume
84
Issue
10

Keywords

biology, force, magnetic particles, magnetic tweezers, manipulation, microfluidic
Created March 8, 2004, Updated February 19, 2017