Integrated air stream micromixer for performing bioanalytical assays on a plastic chip

This paper describes the design, functioning and use of an integrated mixer that relies on air flux to agitate microliter entities of fluid in an embedded microfluidic cavity. The system was fabricated from multiple layers of a thermoplastic elastomer and features circuits for both liquid and air su...

Full description

Saved in:
Bibliographic Details
Published in:Lab on a chip 2014-10, Vol.14 (19), p.375-3761
Main Authors: Geissler, Matthias, Li, Kebin, Zhang, Xuefeng, Clime, Liviu, Robideau, Gregg P, Bilodeau, Guillaume J, Veres, Teodor
Format: Article
Language:English
Subjects:
Agitation
Assaying
Bacteria
Biotechnology - instrumentation
Computational fluid dynamics
Computer Simulation
Design engineering
DNA - analysis
DNA - chemistry
Elastomers - chemistry
Equipment Design
Fluid flow
Holes
Listeria monocytogenes - chemistry
Magnetite Nanoparticles - chemistry
Microfluidic Analytical Techniques - instrumentation
Multiplexing
Nanotechnology - instrumentation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper describes the design, functioning and use of an integrated mixer that relies on air flux to agitate microliter entities of fluid in an embedded microfluidic cavity. The system was fabricated from multiple layers of a thermoplastic elastomer and features circuits for both liquid and air supply along with pneumatic valves for process control. Internally-dyed polymer particles have been used to visualize flow within the fluid phase during agitation. Numerical modelling of the micromixer revealed an overall efficacy of 10 −1 to 10 −2 for momentum transfer at the air-water interface. Simulation of air vortex dynamics showed dependency of the flow pattern on the velocity of the flux entering the cavity. Three bioanalytical assays have been performed as proof-of-concept demonstrations. In a first assay, cells of Listeria monocytogenes were combined with magnetic nanoparticles (NPs), resulting in high-density coverage of the bacteria's surface with NPs after 1 min of agitation. This finding is contrasted by a control experiment without agitation for which interaction between bacteria and NPs remains low. In a second one, capture and release of genomic DNA from fungi through adsorption onto magnetic beads was tested and shown to be improved by agitation compared to non-agitated controls. A third assay finally involved fluorescently-labelled target oligonucleotide strands and polystyrene particles modified with DNA capture probes to perform detection of nucleic acids on beads. Excellent selectivity was obtained in a competitive hybridization process using a multiplexed micromixer chip design. This paper describes the design, functioning and use of an integrated mixer that relies on air flux to agitate microliter entities of fluid in an embedded microfluidic cavity.
ISSN:1473-0197
1473-0189
DOI:10.1039/c4lc00769g