@article{NadernezhadRymaGencetal.2021,
  author    = {Nadernezhad, Ali and Ryma, Matthias and Gen{\c{c}}, Hatice and Cicha, Iwona and J{\"u}ngst, Thomasz and Groll, J{\"u}rgen},
  title     = {Melt electrowriting of isomalt for high-resolution templating of embedded microchannels},
  series = {Advanced Material Technologies},
  volume    = {6},
  journal   = {Advanced Material Technologies},
  number    = {8},
  doi       = {10.1002/admt.202100221},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-256401},
  year      = {2021},
  abstract  = {Fabrication of microchannels using 3D printing of sugars as fugitive material is explored in different fields, including microfluidics. However, establishing reproducible methods for the controlled production of sugar structures with sub-100 μm dimensions remains a challenge. This study pioneers the processing of sugars by melt electrowriting (MEW) enabling the fabrication of structures with so far unprecedented resolution from Isomalt. Based on a systematic variation of process parameters, fibers with diameters down to 20 μm can be fabricated. The flexibility in the adjustment of fiber diameter by on-demand alteration of MEW parameters enables generating constructs with perfusable channels within polydimethylsiloxane molds. These channels have a diameter that can be adjusted from 30 to 200 μm in a single design. Taken together, the experiments show that MEW strongly benefits from the thermal and physical stability of Isomalt, providing a robust platform for the fabrication of small-diameter embedded microchannel systems.},
  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}
}