(3bz) Biomedical Applications of Single-Walled Carbon Nanotubes: Toward Design of Novel Optical Sensors

Semiconducting single-walled carbon nanotubes (SWNTs) are excellent candidates for optical sensors due to their stable fluorescence at near-infrared (nIR) wavelengths without photobleaching. It has been shown that SWNT emission is affected by changes in the local dielectric environment (solvatochromism), electron transfer (doping), or fluorescent quenching. The concepts can be utilized to create sensors for biologically important molecules such as glucose, nitric oxide, hydrogen peroxide, and proteins. Thus, design and synthesis of proper SWNTs wrapping reagents with specific recognition groups play a significant role in constructing a successful sensing interface. Over the past decade or so, polymers have been utilized for noncovalent dispersing of SWNTs in different media. Wrapping of SWNTs could be driven by chemical interactions between SWNTs and the functional groups comprising the polymers, which may include electrostatic interactions, π-π stacking, and hydrogen bonding. Understanding intermolecular interactions between wrapping polymers and SWNTs forms the basis for molecular recognition using fluorescent SWNTs and is essential for the proper design of polymer structures as synthetically selective receptors. My planned research in this area will include the fundamental and applied studies from both sides of experiments and simulation. Namely, to explore this sensing mechanism by designing more polymer-SWNT complexes and to develop novel sensing systems based on our understanding of interactions between SWNT and the polymer.