In my PhD-Thesis I investigated the fast dynamics of alkylglycosides in aqueous solution. This class of substances is of growing interest as these substances are non-toxic, biodegrable surfactants, that are made of renewable ressources.

The Thesis can be downloaded as a pdf-file (~11 MB) here - but only a german version is available yet.

For those, who would like to know more about this research field, I translated the introduction of my PhD-Thesis:

Alkylglycosides are molecules, that consist of a glycoside (a sugar rest) and an alkyl chain (a hydrocarbon chain). As glycosides are hydrophilic (from gr. hydros – water, philos – loving, „water-loving“), while the alkyl chains in contrast are hydrophobic due to their nonpolar structure (vfrom gr. phobos – afraid, „afraid of water“), alkyl glycosides are so-called amphiphilics (from gr. amphis – both, „loving both“). Depending on their surrounding, their concentration, temperature, molecular structure as well as other (outer) parameters, amphiphilics can be found as monomers or as aggregates, like laminar membranes or globular micelles (from nlat.: micella, diminutive for lat.: mica ‚crumb’). The alkyl glycosides that I investigated in my PhD-Thesis all form micelles, when their concentration in aqueous solution is above a certain system-depending concentration called cmc (critical micelle concentration)

These micelles can serve as solubilizing agents for hydrophobic molecules like fats and oils in water. This is the way that most cleaning agents work like. Additionally, this process is used for washing membrane proteins out of their membranes for investigations in aqueous solutions. In the human body bile acid micelles facilitate the digestion of the hydrophobic vitamines A, D, E, and K and some medical drugs can be solubilised in micelles, which allows some kind of drug targeting inside of the human body. In my PhD-Thesis I investigated the so-called monomerexchange process by means of ultrasonic absorption spectroscopy. This allows to determine the reaction constants of this process as well as the (adiabatic) reaction volume. The dependence of these values from the distinct headgroups or the length of the alkyl chain can be obtained to learn more about the influence of the molecular structure on the micellar kinetics.

A special focus of my PhD-Thesis lies on the investigation of molecular conformational changes of the sugar parts of the molecules. Especially the question is investigated if and in which way the surrounding of the molecules has an influence on the conformational kinetics. The differences between the monomer situation, where each surfactant molecule is surrounded by water only and the micellar situation, where some of the surfactant molecules are surrounded by 'micelle neighbors' can serve as a simple model for so-called induced-fit-complexes and shed light on the question of the influence of steric hindrances of neighbor molecules on conformational kinetics.