Chemical and Biological Microassays in Freely Suspended Droplets on Novel Fluidic Chips

Abstract

We developed the principles of a platform for manipulation of freely suspended micro- and nanoliter droplets for micromanipulation and microassays. The liquid transport in such chips requires very low energy input due to the lack of microchannels or solid walls present in conventional microfluidic devices. Water droplets float on the surface of a denser perfluorinated liquid and are driven by alternating or constant electric fields created by addressable arrays of electrodes immersed in the oil. The ability to manipulate droplets from suspensions, and to observe the dynamics of particles inside them revealed charge and polarization effects that affect the dynamics of the droplets and thermal gradient effects that lead to separation of the particles into either the top or bottom part of the droplet. These effects can be conducive to carrying rapid agglutination assays, as they allow pre- concentration of the particles. We demonstrated a few chemical precipitation reactions inside the droplets and observed the dynamics of live cells suspended and transported within the droplet microcarriers. The results provide insights on the potential use of the droplet microfluidic platform to parallel assays on the microscale.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 2004
Accession Number
ADA424968

Entities

People

  • Orlin D. Velev

Organizations

  • North Carolina State University

Tags

Communities of Interest

  • Advanced Electronics
  • Sensors

DTIC Thesaurus Topics

  • Chemical Engineering
  • Chemical Precipitation
  • Chemical Reactions
  • Chemistry
  • Dielectric Permittivity
  • Electric Fields
  • Electrodes
  • Encapsulation
  • Frequency
  • Fungi
  • Materials Science
  • Nanoparticles
  • Particles
  • Polarization
  • Precipitation
  • Surface Tension
  • Temperature Gradients

Readers

  • Aerosol Science/Aerosol Physics
  • Combustion and Flow Dynamics.