Controllable charge transfer via DNA molecules

• Main Author: Liu, Yuanjun
• Other Authors: -
• Format: Thesis-Doctor of Philosophy
• Language: English
• Published: Nanyang Technological University 2015
• Subjects: DRNTU::Science::Chemistry::Biochemistry::Spectroscopy; DRNTU::Engineering::Materials::Photonics and optoelectronics materials; DRNTU::Engineering::Nanotechnology; DRNTU::Science::Chemistry::Physical chemistry::Electrochemistry
• Online Access: http://hdl.handle.net/10356/65551
• Institution: Nanyang Technological University

Electron transfer is the most essential process in any chemical or biochemical reactions. Especially, the movement of electrons in biological system is essential for life processes. Charge transfer via DNA molecules has been studied for decades. Double helix DNA structure with closed packed π stack has been considered to mediate long-range charge transfer. Although the comprehensive fundamental description of charge transfer along DNA is still missing, the process can be categorized into oxidative holes and reductive electrons transfer/transport. Hence, this thesis focused on investigation and actively control of charge transfer via DNA and DNA complex nanostructures. With rational design, the DNA based electrical nanodevices can achieve controllable performance. Dye molecules interaction is one of convenient perturbation method to enhance charge transfer along DNA. Thermally controllable charge transport via DNA molecules will also be presented in this thesis. In addition, electrochemically modulated charge transfer is utilized and investigated. Potential-dependent Raman responses, which are corresponding to redox switching and fluctuant electromagnetic enhancement caused by electro-triggered LSPR shift of substrate, allow us to characterize the electrochemical process with intensity variation of representative Raman bands as a function of potentials. Meanwhile, based on the advantage of high spatial resolution, the process of electron transfer along dsDNA chains have been specifically aimed by judicious choice of DNA intercalator on a heterogeneously modified electrode surface, providing a powerful tool to study heterogeneous reactions during electroanalysis. As consequence, this project is aiming to develop novel integrated nanostructure-biomolecule hybrid devices for both application and fundamental study based on nanofabrication and focus on thermally/electrochemically/optically multi-modulated nanodevices based on DNA complex with the combination of nanoelectronics and plasmonics.