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Charged Entities Interacting with Electronically Responsive Structures with Implications for the Modeling of Interactions between Carbon Nanotubes and DNA
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- Author / Creator
- Malysheva, Oxana
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Understanding interactions between charged entities with electronically responsive
structures embedded in an electrolytic environment is important because of the diverse
range of practical applications. This study was motivated by the technique
where single stranded DNA was used to separate carbon nanotubes (CNTs) with
different electronic properties (metallic or semiconducting).
The objective of this study was to create theoretical models which improve the
understanding of the DNA-assisted separation technique for CNTs. In the course
of this study four models with different levels of complexity at the continuum level
were developed, with the electrostatic interaction being the main focus. In each of
these models, with certain simplifications on geometry the boundary value problems
for the electric potential were formulated using equations of electrostatics and
in particular the Debye-Huckel theory for electrolyte. Using mathematical techniques,
semi-analytical solutions for the electric potential were obtained and its implication
for the DNA-CNT interaction and the property of the DNA-CNT hybrid
were discussed. It was found that the electric potential due to a metallic CNT-DNA
hybrid is weaker than that for a semiconducting CNT-DNA. In addition to that based
on the proposed models, it was observed that the obtained results are applicable to
a larger class of problems involving charged entities interacting with responsive
structures. For example, it was studied how the phenomenon of counterion condensation
on a polyelectrolyte (PE) is affected by the presence of a responsive cylinder.
It was shown that counterions gradually release from the surface of the PE as it
approaches a metallic cylinder, whereas more counterions are condensed on the PE
as it approaches a dielectric cylinder where the dielectric constant of that cylinder
ia smaller than that of the electrolyte solution.
Results from this dissertation clearly demonstrate that in order to model the
interaction between a charged entity and an electronically responsive structure, it is
crucial to account for the response of the structure. Therefore, the models developed
here have implications for modeling interactions between other charged entities
near responsive structures. For example, cells adhering to an implant’s surface and
biosensors detecting a specific DNA sequence. -
- Subjects / Keywords
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- Graduation date
- Fall 2011
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- Type of Item
- Thesis
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- Degree
- Doctor of Philosophy
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- License
- This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.