Physical Sciences and Mathematics Commons^™

A Novel Integrated Platform Combining Atomic Force Microscopy And Fluorescence Correlation Spectroscopy, Venkatesh Subba Rao

Wayne State University Dissertations

At the nanoscale near an interface, the discrete nature of liquids is expected to influence various properties, such as density, viscosity or diffusion constants. Understanding interfacial properties of liquids is important for the development of nanotechnology, especially for the fields of nano-rheology and nano-tribology, and also for understanding various mechanisms in biological systems at the molecular level, such as protein folding or the self-assembly of lipid vesicles, which invariably involve liquids. Atomic force microscope (AFM) and fluorescence correlation spectroscope (FCS) are two complimentary techniques that are commonly employed investigate mechanics and dynamics of liquids at interfaces. In this thesis, the …

Investigation Of Protein-Protein Interaction Using Atomic Force Microscopy, Essa Yousef Mayyas

Wayne State University Dissertations

Single-molecule approaches to measuring the kinetics of protein dissociation have the advantage that measurements can be performed in native environments, such as living cells, where concentrations of target molecules may be quite low. In addition, single molecule approaches allow for the measurement of variances in protein kinetics, thus providing a more complete picture of protein kinetics than ensemble techniques which typically only provide averages.

In our laboratories, we use the force spectroscopy (FS) technique to study protein binding and dissociation. FS measures the strength of the protein molecules bond with high resolution down to pico-Newton either on the surface of …

Measuring The Nanomechanics Of Nanoconfined Water Layers, Shah Haidar Khan

Wayne State University Dissertations

Nanoconfined water has been the subject of special interest due to its applications in various fields such as biology, geology, medicine, and engineering tribology. While there is a general agreement on the layering of water molecules along atomically smooth surfaces, the behavior and properties of nanoconfined water is still poorly understood. A significant controversy exists whether there is a phase transformation imposed by confinement. We have measured the stiffness and damping coefficient of nanoconfined water using a small amplitude (0.5-1 Å) atomic force microscope. The results were analyzed with the help of two viscoelastic models, the Kelvin model and the …