E: Nano-Biology

During the last decade, a multitude of new and innovative materials, analytical tools, and manufacturing techniques have been evolved in the field of nanosciences. In the interdisciplinary Research area E biologists, chemists, and physicists explore the interactions of cells with bio-functionalized nanoparticles and nanostructured surfaces in order to study and manipulate cellular function. Cellular reactions are monitored with novel nano-analytical tools including advanced light microscopy. The overall future aim of our basic and applied research is to allocate novel nano-materials for biotechnological and medical problems.

In project E1 nanoparticles are functionalized with cell penetrating peptides and synthetic polymers to transport nano-scale cargo across the lipid membrane barrier into living cells. These constructs are specifically designed for applications in a biological context, e.g., to bind to intracellular substructures, to manipulate cells via electric/magnetic field gradients, or for drug delivery. To be able to understand and optimize the working mechanisms of these novel bio-nano tools, their molecular interactions occurring at the level of the lipid bilayer and the dynamic cellular events in time and space have to be characterized in detail.

During the last decade, physical properties – in addition to growth factors, signaling- and adhesion-molecules – in the extracellular environment have been recognized to have a profound influence on cell behavior and differentiation. These physical stimuli include mechanical stiffness and topography of the cellular environment, as well as spatial patterns of ligand presentation at the nanoscale. The overall aim of project E2 is to manipulate cell behavior and cell differentiation via biochemically and mechanically tailored two-dimensional (2D) substrates and three-dimensional (3D) scaffolds. The development of novel cell culture substrates and bio-functionalization methods will break new ground to systematically investigate the effects of spatial ligand distributions and scaffold stiffness on cell behavior in three-dimensional environments.

Super-Resolution Optical Microscopy

Light microscopy is a key technique for the study of living systems because it allows cells and tissues to be imaged in all three spatial dimensions over long periods of time under minimally invasive, near-physiological conditions. Unfortunately, conventional light microscopy is limited to a resolution of about 200 nm. As typical biological macromolecules have dimensions on the nanometer scale, their structures and interactions cannot be resolved by conventional light microscopy. Project E4 focuses on the development and application of advanced light-microscopy methods to study biomolecular processes in living cells approaching molecular resolution. The activities include the development of super-resolution imaging techniques for live-cell analysis, new tools for advanced data processing and the design of new fluorescent markers.