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Abstract Dielectrophoresis is a well‐understood phenomenon that has been widely utilized in biomedical applications. Recent advancements in miniaturization have contributed to the development of dielectrophoretic‐based devices for a wide variety of biomedical applications. In particular, the integration of dielectrophoresis with microfluidics, fluorescence, and electrical impedance has produced devices and techniques that are attractive for screening and diagnosing diseases. This review article summarizes the recent utility of dielectrophoresis in assays of biomarker detection. Common screening and diagnostic biomarkers, such as cellular, protein, and nucleic acid, are discussed. Finally, the potential use of recent developments in machine learning approaches toward improving biomarker detection performance is discussed. This review article will be useful for researchers interested in the recent utility of dielectrophoresis in the detection of biomarkers and for those developing new devices to address current gaps in dielectrophoretic biomarker detection.
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Trapping proteins on nanopores by dielectrophoresis
Interest in the phenomenon of dielectrophoresis has gained significant attention in recent years due to its potential for sorting, manipulation, and trapping of solutes, such as proteins, in aqueous solutions. For many decades, protein dielectrophoresis was considered impossible, as the predicted magnitude of the force arising from experimentally accessible field strengths could not out-compete thermal energy. This conclusion was drawn from the mainstay Clausius–Mossotti (CM) susceptibility applied to the dielectrophoretic force. However, dielectric interfacial polarization leading to the CM result does not account for a large protein dipole moment that is responsible for the dipolar mechanism of dielectrophoresis outcompeting the CM induction mechanism by three to four orders of magnitude in the case of proteins. Here, we propose an explicit geometry within which the dipolar susceptibility may be put to the test. The electric field and dielectrophoretic force are explicitly calculated, and the dependence of the trapping distance on the strength of the applied field is explored. A number of observable distinctions between the dipolar and induction mechanisms are identified.
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- Award ID(s):
- 2154465
- PAR ID:
- 10493967
- Publisher / Repository:
- AIP
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 133
- Issue:
- 16
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0144564
