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Updated: Jul 14, 2026

Separation of Bioactive Small Molecules, Peptides from Natural Sources and Proteins from Microbes by Preparative Isoelectric Focusing (IEF) Method
Published on: June 14, 2020
Electric field isolator (EFI) for isolated and electrophoretic manipulation of charged biomolecules
Jae Young Yun1, Sang Jun Mun, Seung S Lee
1Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea. mappers@kaist.ac.kr
Abstract:
This paper describes a novel technology-an electric field isolator (EFI)-that can be used for achieving isolated and electrophoretic manipulation of charged biomolecules inside a selected microscopic location. The EFI is a ground ring-shaped electrode (RE) surrounding a centre electrode (CE), which is comprised of a functional unit. When the CE is powered, the ground RE can inhibit the electric field from spreading to the neighbouring functional units. Therefore, the electrophoretic movement of the charged molecules in an electric field, which is based on the principle similar to that of electrophoresis, can be isolated inside a selected location. The ground RE causing this phenomenon is referred to as the EFI. In this paper, we clearly show the functionality of the EFI with mathematical and experimental studies.
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