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Free Flow Ion Concentration Polarization Focusing (FF-ICPF).

ABSTRACT: Electrokinetic separation techniques in microfluidics are a powerful analytical chemistry tool, although an inherent limitation of microfluidics is their low sample throughput. In this article we report a free-flow variant of an electrokinetic focusing method, namely ion concentration polarization focusing (ICPF). The analytes flow continuously through the system via pressure driven flow while they separate and concentrate perpendicularly to the flow by ICPF. We demonstrate free flow ion concentration polarization focusing (FF-ICPF) in two operating modes, namely peak and plateau modes. Additionally, we showed the separation resolution could be improved by the use of an electrophoretic spacer. We report a concentration factor of 10 in human blood plasma in continuous flow at a flow rate of 15 ?L min-1.

SUBMITTER: Papadimitriou VA

PROVIDER: S-EPMC7143306 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Free Flow Ion Concentration Polarization Focusing (FF-ICPF).

Papadimitriou Vasileios A VA Segerink Loes I LI Eijkel Jan C T JCT

Analytical chemistry 20200330 7

Electrokinetic separation techniques in microfluidics are a powerful analytical chemistry tool, although an inherent limitation of microfluidics is their low sample throughput. In this article we report a free-flow variant of an electrokinetic focusing method, namely ion concentration polarization focusing (ICPF). The analytes flow continuously through the system via pressure driven flow while they separate and concentrate perpendicularly to the flow by ICPF. We demonstrate free flow ion concent ...[more]

PMID: 32195578

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