Research
Our research interests are primarily in the field of organic and polymer chemistry andinvolve the synthesis, characterization and evaluation of fluorophore, smalltherapeutically active molecules and chemically defined carriers, nanomedicine andbiosensing. Examples include ultrastable NIR absorbing rylene dyes for site-selectivelabeling of proteins in living cells, pharmaceutical carriers for immunoassays of cancer andbioorthogonal modification of therapeutic peptides and proteins
Guanidinium containing polymers
Our work is focused on the design of positively charged polymethacryamide based carriersthat are applied for the delivery of DNA or siRNA. In addition to the influence of themonomers, we also investigate the advantages and disadvantages of the incorporation ofhydrophobic and cationic monomers, their arrangement in linear polymers (statistical,gradient, block-shaped) with regard to their binding affinity, transfection efficiency, thecondensation efficiency of DNA and as well as the size of the resulting polyplexes.
Photostable chromophore for biological and medical applications
One commonly used method capable of untangling the internalization pathway that drugcarriers take inside the cell is near infrared (NIR) fluorescence imaging. However the qualityand reproducibility of the data recorded with this technique are strictly dependent on thephotophysical properties of fluorescent dyes used as reporters. Recently, we introduced afacile preparation method for NIR absorbing perylene monoimide that are highlybiocompatible. Fluorescence microscopy imaging in living and fixed cells stained with thesechromophores demonstrate exceptional photostability and efficient subcellular targetingusing small chemical groups such as triphenylphosphine.
Photosensitizers for photocatalytic water splitting
We are working on the design of tailored rylene photosensitizers with broad visible lightabsorption, capable of transferring electrons to catalytically active sites. Chemicalfunctionalization of the rylene scaffold is used to enable coupling of the chromophores tocatalytic units, for soft matter integration and to tune the redox potentials of the dye toachieve efficient electron transfer to the catalytic center as well as to mediate its solubility.Photophysical investigation of the photosensitizers and coupled photosensitizers-catalystsystems provides a deeper understanding of the electron transfer processes as well asdeactivation and degradation pathways to identify general design guidelines for novelphotosensitizers for hydrogen reduction.
