Barrier properties of biological hydrogel filters

• Applicant: Professor Dr. Oliver Lieleg
• Subject Area: Biophysics
• Term: from 2012 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 225109143

The aim of this project is to characterize the barrier properties of two important biological hydrogels in vitro: vitreous humor and neurofilament gels. A key aspect of this study is to elucidate the contribution of electrostatic interactions to the regulation of particle diffusion inside the hydrogels. We will use test particles with well-defined properties such as particle size and surface charge and will quantify their diffusion behavior in the hydrogel environments. The insights obtained from the experiments with vitreous humor and neurofilament gels will be compared with previous results on particle diffusion in mucus and extracellular matrix to help us identify the biochemical key motifs that establish selective filtering in biological hydrogels.So far, the barrier function of biological hydrogels has mainly been studied by medical researchers in vivo using animal models or complex ex vivo tissues. However, in those complex systems it is highly difficult to relate the observed effects to their microscopic origins. Here, we will overcome this limitation by studying (partially) purified and reconstituted hydrogel systems which will give us a much broader range of control over the experimental conditions than it is possible with native samples. The anticipated results from this project will not only provide us with a better understanding of the physical principles that regulate diffusion in biological hydrogels, but will also pinpoint design strategies for the development of new drug delivery agents or hydrogels with biomedical applications such as implant coatings or artificial tissues. Therefore, this project will establish an important link between polymer physics, cell biology, medical engineering and drug delivery.

• DFG Programme: Research Grants