Antibodies are a crucial part of the immune system and increasingly used for therapeutic purposes. Due to the strong dependance of conformations of these large protein molecules and ensuing intermolecular forces on local conditions, antibodies are prone to both adsorption at interfaces and formation of aggregates. In this master's thesis, the processes were monitored in two ways. We measured the adsorption dynamics of protein films at the water-air phase boundary using Brewster angle microscopy (BAM) by puncturing films of two antibodies in a controlled manner and monitoring changes in reflectivity during their reconstitution. From the data, we determined the dependance of reconstitution speed on antibody concentrations; at a concentration of $\mathrm{0.1\ mg/mL}$, for example, the film fully reforms in a timespan of $\mathrm{10\ s}$. At the precision of the measurements carried out, a systematic difference between the observed protein types could not be detected. We modelled the process with a simple 2D model based on the finite element method and an improved 3D model of precursor-mediated adsorption. Additionally, we subjected the protein films to controlled agitation and analysed the aggregated protein particles using optical microscopy. Images of container bottoms of agitated samples were periodically taken and a script was developed for their automatic analysis. For both observation methods, we also examined the effect of surfactant molecules on reconstitution/aggregation. Concentration limits for the formation of a viscoelastic film and aggregation were significantly below the critical micelle concentration of surfactants.
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