@article{LiebscherTessmarGroll2020, author = {Liebscher, Julia and Teßmar, Joerg Karl and Groll, J{\"u}rgen}, title = {In Situ Polymer Analogue Generation of Azlactone Functions at Poly(oxazoline)s for Peptide Conjugation}, series = {Macromolecular Chemistry and Physics}, volume = {221}, journal = {Macromolecular Chemistry and Physics}, number = {1}, doi = {10.1002/macp.201900500}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-208147}, pages = {1900500}, year = {2020}, abstract = {The physical and chemical stability of peptides for biomedical applications can be greatly enhanced through the conjugation of polymers. A well-known but rather underemployed selective coupling functionality is the azlactone group, which readily reacts with a number of different nucleophiles without the need for activation and the formation of any by-products. For example, azlactone functional polymers are used to react with peptides and proteins, rich in amino and thiol groups, to form polymeric beads for affinity-based column chromatography. So far, side chain functional azlactone polymers have been mainly synthesized by radical polymerization using 2-vinyl-4,4-dimethyl azlactone together with different acrylate monomers. Here, a new azlactone precursor equipped with a functional thiol is presented, which can be attached to any vinyl functional polymer by thiol-ene chemistry. Subsequently, the formation of the reactive azlactone ring can be performed in situ at high conversion rate without the need for illumination. This approach is tested on an azlactone side functional poly(2-oxazoline) by coupling amine containing molecules including a model peptide and is proven via \(^1\)H NMR spectroscopy, IR spectroscopy, as well as HPLC measurements.}, language = {en} } @article{RymaTylekLiebscheretal.2021, author = {Ryma, Matthias and Tylek, Tina and Liebscher, Julia and Blum, Carina and Fernandez, Robin and B{\"o}hm, Christoph and Kastenm{\"u}ller, Wolfgang and Gasteiger, Georg and Groll, J{\"u}rgen}, title = {Translation of collagen ultrastructure to biomaterial fabrication for material-independent but highly efficient topographic immunomodulation}, series = {Advanced materials}, volume = {33}, journal = {Advanced materials}, number = {33}, doi = {10.1002/adma.202101228}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256381}, year = {2021}, abstract = {Supplement-free induction of cellular differentiation and polarization solely through the topography of materials is an auspicious strategy but has so far significantly lagged behind the efficiency and intensity of media-supplementation-based protocols. Consistent with the idea that 3D structural motifs in the extracellular matrix possess immunomodulatory capacity as part of the natural healing process, it is found in this study that human-monocyte-derived macrophages show a strong M2a-like prohealing polarization when cultured on type I rat-tail collagen fibers but not on collagen I films. Therefore, it is hypothesized that highly aligned nanofibrils also of synthetic polymers, if packed into larger bundles in 3D topographical biomimetic similarity to native collagen I, would induce a localized macrophage polarization. For the automated fabrication of such bundles in a 3D printing manner, the strategy of "melt electrofibrillation" is pioneered by the integration of flow-directed polymer phase separation into melt electrowriting and subsequent selective dissolution of the matrix polymer postprocessing. This process yields nanofiber bundles with a remarkable structural similarity to native collagen I fibers, particularly for medical-grade poly(ε-caprolactone). These biomimetic fibrillar structures indeed induce a pronounced elongation of human-monocyte-derived macrophages and unprecedentedly trigger their M2-like polarization similar in efficacy as interleukin-4 treatment.}, language = {en} }