Probing Changes at the Lipid-Water Interface via Xe-129 NMR : Dynamical and Structural Changes of Fully Hydrated Lipid Vesicles Characterized by Chemical Shift Analysis

ISBN-13: 9783845471532 / Angielski / Miękka / 2011 / 180 str.

Caroline Keenan

Opis

Thermally and hyperpolarized Xe-129 NMR spectroscopy are used to investigate gas transfer and adsorption between aqueous and lipid bilayer phases via changes in the Xe-129 chemical shift. The large electron cloud of the xenon atom is very sensitive to even slight modifications in its local environment, manifesting as changes in the experimentally observed chemical shift value. Thermodynamic and kinetic information are extracted by monitoring this shift with changing external variables and fit to a mathematical model in order to extract pertinent parameters. Partitioning behavior as related to increasing molecular stress and changing lipid morphology is studied in addition to the potential existence of intermediate lipid phases. Lastly, Anodic Aluminum Oxide (AAO) substrate was utilized to stabilize bilayers in the magnetic field, facilitating the study of Xe diffusivity between phases using 2D-exchange NMR methods. Results are discussed in context of anesthetic action and the lateral pressure profile.

O autorze

Dr. Keenan received her Ph.D. in 2009 in Physical Chemistry from the University of Florida under the supervision of Dr. C. R. Bowers. She is currently a post-doctoral research associate at the University of Bayreuth, Germany, developing a hyper-polarization generator to be used with solid-state NMR techniques and NMR crystallographic methods.