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Gewählte Doctoral Thesis:

Tuchpong Choosri (2010): DEVELOPMENT OF EXPERIMENTAL METHODS FOR THERMODYNAMIC PROPERTIES OF AQUEOUS PROTEIN AND SALT SOLUTIONS.
Doctoral Thesis - Studienabteilung, BOKU-Universität für Bodenkultur, pp 115. UB BOKU obvsg

Data Source: ZID Abstracts
Abstract:
The knowledge of thermodynamic properties of aqueous solutions of electrolytes and proteins is very important for the understanding, design and optimization of chemical and biochemical engineering processes. Here, precise experimental methods for thermodynamic properties of aqueous salt and protein solutions were developed. Water activity is a very important property to describe aqueous solutions. It is, e.g., a measure for the microbiological activity in such solutions. Here, a completely new method to measure the water activity by Fourier Transform Infrared (FTIR) spectroscopy was developed. The new FTIR method is quite fast, very accurate and reliable when compared to literature data. In biochemical systems, protein folding is a very important phenomenon. Adsorption has a very strong effect on protein folding and stability. Protein folding was studied by micro DSC (differential scanning) calorimetry. The method was improved to gain very reliable data on the unfolding enthalpy and melting temperature for the example of lysozyme adsorbed from aqueous Hepes buffer solutions on silica particles. The water activity of the solutions were varied through different sodium and calcium chloride concentrations which has no influence on the stability of the adsorbed proteins but a significant influence on the native and desorbed proteins. Adsorption of lysozyme was shown to be only incompletely reversible.

Betreuer: Wendland Martin

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