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Title: Magnetic Tools for Lab-on-a-chip Technologies

Abstract

This study establishes a set of magnetics-based tools that have been integrated with microfluidic systems. The overall impact of the work begins to enable the rapid and efficient manipulation and detection of magnetic entities such as particles, picoliter-sized droplets, or bacterial cells. Details of design, fabrication, and theoretical and experimental assessments are presented. The manipulation strategy has been demonstrated in the format of a particle diverter, whereby micron-sized particles are actively directed into desired flow channels at a split-flow junction by means of integrated microelectromagnets. Magnetic detection has been realized by deploying Giant Magnetoresistance (GMR) sensors--microfabricated structures originally developed for use as readout elements in computer hard-drives. We successfully transferred the GMR technology to the lab-on-a-chip arena, and demonstrated the versatility of the concept in several important areas: real-time, integrated monitoring of the properties of multiphase droplet flows; rapid quantitative determination of the concentration of magnetic nanoparticles in droplets of ferrofluids; and high-speed detection of individual magnetic microparticles and magnetotactic bacteria. The study also includes novel schemes for hydrodynamic flow focusing that work in conjunction with GMR-based detection to ensure precise navigation of the sample stream through the GMR detection volume, therefore effectively establishing a novel concept of a microfabricatedmore » magnetic flow cytometer.« less

Authors:
 [1]
  1. Iowa State Univ., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Lab., Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
892722
Report Number(s):
IS-T 1942
TRN: US200623%%555
DOE Contract Number:
W-7405-Eng-82
Resource Type:
Thesis/Dissertation
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BACTERIA; CELL FLOW SYSTEMS; COMPUTERS; DESIGN; DETECTION; FABRICATION; FOCUSING; HYDRODYNAMICS; LIQUIDS; MAGNETIC MATERIALS; MAGNETORESISTANCE; MONITORING; NAVIGATION

Citation Formats

Pekas, Nikola Slobodan. Magnetic Tools for Lab-on-a-chip Technologies. United States: N. p., 2006. Web. doi:10.2172/892722.
Pekas, Nikola Slobodan. Magnetic Tools for Lab-on-a-chip Technologies. United States. doi:10.2172/892722.
Pekas, Nikola Slobodan. Sun . "Magnetic Tools for Lab-on-a-chip Technologies". United States. doi:10.2172/892722. https://www.osti.gov/servlets/purl/892722.
@article{osti_892722,
title = {Magnetic Tools for Lab-on-a-chip Technologies},
author = {Pekas, Nikola Slobodan},
abstractNote = {This study establishes a set of magnetics-based tools that have been integrated with microfluidic systems. The overall impact of the work begins to enable the rapid and efficient manipulation and detection of magnetic entities such as particles, picoliter-sized droplets, or bacterial cells. Details of design, fabrication, and theoretical and experimental assessments are presented. The manipulation strategy has been demonstrated in the format of a particle diverter, whereby micron-sized particles are actively directed into desired flow channels at a split-flow junction by means of integrated microelectromagnets. Magnetic detection has been realized by deploying Giant Magnetoresistance (GMR) sensors--microfabricated structures originally developed for use as readout elements in computer hard-drives. We successfully transferred the GMR technology to the lab-on-a-chip arena, and demonstrated the versatility of the concept in several important areas: real-time, integrated monitoring of the properties of multiphase droplet flows; rapid quantitative determination of the concentration of magnetic nanoparticles in droplets of ferrofluids; and high-speed detection of individual magnetic microparticles and magnetotactic bacteria. The study also includes novel schemes for hydrodynamic flow focusing that work in conjunction with GMR-based detection to ensure precise navigation of the sample stream through the GMR detection volume, therefore effectively establishing a novel concept of a microfabricated magnetic flow cytometer.},
doi = {10.2172/892722},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}

Thesis/Dissertation:
Other availability
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