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Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Continuous-flow biomolecule and cell concentrator by ion concentration polarization
Rhokyun Kwak1, Sung Jae Kim, Jongyoon Han
1Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Analytical Chemistry
|August 23, 2011
Summary
This study introduces a novel nanofluidic device for continuous biomolecule and cell concentration using ion concentration polarization (ICP). The system achieves up to 100-fold concentration, ideal for biosensor applications.
Area of Science:
- Nanofluidics
- Biomolecule concentration
- Biosensor technology
Background:
- Effective pre-concentration of biomolecules and cells is crucial for enhancing biosensor sensitivity.
- Existing methods often face challenges with continuous flow and integration.
Purpose of the Study:
- To develop a continuous-flow nanofluidic device for concentrating biomolecules and cells.
- To utilize ion concentration polarization (ICP) for efficient sample manipulation.
- To create a versatile front-end for various biosensing platforms.
Main Methods:
- Fabrication of a microfluidic device with a Nafion nanojunction.
- Application of an electric field to induce ICP and guide targets.
- Control of hydrodynamic resistance for adjustable concentration factors.
- Demonstration with diverse targets including bacteria, proteins, and cells.
Main Results:
- Achieved continuous-flow concentration with factors up to 100-fold.
- Successfully concentrated fluorescein sodium salt, rGFP, RBCs, E. coli, and FITC-lectin.
- Demonstrated adaptability across different buffer conditions.
- Validated the system's potential as a generic concentration front-end.
Conclusions:
- The developed nanofluidic concentrator offers efficient, continuous pre-concentration for biosensing.
- ICP-based manipulation provides a robust mechanism for biomolecule and cell enrichment.
- The system's design allows for minimal integration complications with existing biosensors.
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