Academic Education

Academic Career

Expertise

• In the carbohydrate materials group, we aim to expand the fundamental understanding of carbohydrate and apply this knowledge to create designer carbohydrate-based materials. We use automated glycan assembly (AGA) to synthesize well-defined oligosaccharides as probes for structural analysis. With molecular dynamics (MD) simulations, NMR spectroscopy, and crystallographic analysis, we have demonstrated that different classes of polysaccharides adopt fundamentally different conformations, such as helices or rod-like structures, which can be disrupted by single-site substitution. Much focus is given to the visualization of oligosaccharides at the single molecule level. The combination of electrospray ionization (ESI) and scanning tunneling microscopy (STM) at low temperature, allowed us to visualize recurrent structural features with subnanometer resolution (in collaboration with the MPI-FKF).Our synthetic approach allowed us to prepare a collection of cellulose and chitin derivatives, bearing modifications in specific positions of the chain (e.g. methylation, fluorination, charges). We have demonstrated that the systematic hydrogen bond manipulation, not only alter the single chain conformation, but also drastically affects the solubility, aggregation behavior, and crystallinity of the material. These simple synthetic oligosaccharides self-assemble into nanostructures of varying morphologies. Differences in chain length, monomer modification, and aggregation methods yielded glycomaterials with distinct shapes and unexpected optical properties. This finding is particularly important in the prospective of creating novel carbohydrate materials with tunable properties.