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We present a nanofluidic device enabling single-molecule confinement through free-energy landscapes created by dynamic electrical gating of embedded nanoelectrodes. Unlike static geometric confinement, this system uses a parallel electrode configuration with nanoelectrodes placed in a dielectric layer. Localized electrokinetic fields at electrode wells form tunable attractive potential wells for bimolecular capture. By modulating the voltage bias waveform, the device allows precise control over confinement dynamics, enabling molecular capture, release, and exposure to periodic or stochastic confinement regimes. This flexibility facilitates the study of biomolecular behavior under dynamically adjustable conditions, including controlled confinement fluctuations. The device can manipulate diverse analytes such as double-stranded DNA, liposomes, and DNA nanotubes and facilitates introducing molecules into confined environments intact from bulk while providing enhanced tunability. With the ability to implement tailored confinement profiles, this platform represents a versatile tool for probing molecular confinement and behavior in complex, dynamically varying environments.
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Nanofluidic charged-coupled devices for controlled DNA transport and separation
Abstract Controlled molecular transport and separation is of significant importance in various applications. In this work, we presented a novel concept of nanofluidic molecular charge-coupled device (CCD) for controlled DNA transport and separation. By leveraging the unique field-effect coupling in nanofluidic systems, the nanofluidic molecular CCD aims to store charged biomolecules such as DNAs in discrete regions in nanochannels and transfer and separate these biomolecules as a charge packet in a bucket brigade fashion. We developed a quantitative model to capture the impact of nanochannel surface charge, gating voltage and frequency, molecule diffusivity, and gating electrode geometry on the transport and separation efficiency. We studied the synergistic effects of these factors to guide the device design and optimize the DNA transport and separation in a nanofluidic CCD. The findings in this study provided insight into the rational design and implementation of the nanofluidic molecular CCD.
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- Award ID(s):
- 1710831
- PAR ID:
- 10326648
- Date Published:
- Journal Name:
- Nanotechnology
- Volume:
- 32
- Issue:
- 34
- ISSN:
- 0957-4484
- Page Range / eLocation ID:
- 345501
- 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/10.1088/1361-6528/ac027f
