Biocompatible polymeric inks

Photo-crosslinked acrylates offer the possibility of developing and supplying suitable materials which meet the requirements of additive manufacturing (AM) and which can be used as materials for medical application fulfilling the requirements of biocompatibility and long-term stability. Their mechanical properties can be adjusted in a wide range and they are suitable for applications ranging from dental fillings to contact lenses.

Synthetic biocompatible resins are a cost effective material class suitable for various AM technologies such as stereolithography (STL, SLA, MPP, TPP), 3D inkjet and extruder dispersion printing techniques.

At Fraunhofer new polymeric and hybrid photo-crosslinkable materials are developed that meet AM process-related boundary conditions, e.g  keeping within viscosity limits, achieving three-dimensional UV crosslinking, and curing by visible laser light. The range of developed materials covers up soft elastic materials e.g. for development of artificial blood vessel equivalents to hard bone-like materials. Also (water) soluble or mechanical removable support-materials have been developed.

Services#

Design, synthesis and formulation of functional resins (inks) for 3D printing application:

Resin composition

  • Crosslinkable polymers, crosslinkers, reactive diluents, photoinitiators:
  • Control of viscosity (-> printing process)
  • Control of light sensitivity (-> selective curing)
  • Increased cure speed
  • Controlling O2 sensitivity -> better controlling inert inkjet printing

Crosslinked material

  • Control of elongation strength and tensile strenght
  • E-modulus: soft material (1 MPa) -> stiff material (2500 MPa)
  • Swellability: hydrophobic ( 0 %) -> hydrophilic (200+ %)
  • Surface functionality: double bonds, carboxy-functions, amino-functions
  • Shape memory polymers

Patents#

  • Photocrosslinking elastomers for rapid prototyping, WO2012041519A2
  • Device and method for the production of 3d structures in layers, and use thereof, WO2012041522A1

Publications#

  • Engelhardt, S.; Hoch, E.; Borchers, K.; Meyer, W.; Krüger, H.; Tovar, G.; Gillner, A.
    Fabrication of 2D Protein Microstructures and 3D Polymer–protein Hybrid Microstructures by Two-Photon Polymerization.
    Biofabrication 3 (2011): 25003.
  • Engelhardt, S.; Hu, Y.; Seiler, N.; Riester, D.; Meyer, W.; Krüger, H.; Wehner, M.; Bremer-Koebberling, E.; Gillner, A. 3D-Microfabrication of Polymer-Protein Hybrid Structures with a Q-Switched Microlaser.
    6, no. 1 (2011): 54–58. doi:10.2961/jlmn.2011.01.0012.
  • Grothe, D.C.; Meyer, W.; Janietz, S.
    Acrylate Functionalized Tetraalkylammonium Salts with Ionic Liquid Properties.
    Molecules 17, no. 6 (May 31, 2012): 6593–6604. doi:10.3390/molecules17066593.
  • Hoch, E.; Schuh, C.; Hirth, T.; Tovar, G.; Borchers, K.
    Stiff gelatin hydrogels can be photo-chemically synthesized from low viscous gelatin solutions using molecularly functionalized gelatin with a high degree of methacrylation.
    Journal of Materials Science: Materials in Medicine 11 (2012) 2607-2617.
  • Huber, B.; Engelhardt, S.; Meyer, W.; Krüger, H.; Wenz, A.; Schönhaar, V.; Tovar, G.; Kluger, P.; Borchers, K.
    Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization.
    Journal of Functional Biomaterials 7, no. 2 (April 20, 2016): 11. doi:10.3390/jfb7020011.
  • Meyer, W.; Engelhardt, S.; Novosel, E.; Elling, B.; Wegener, M.; Krüger, H.
    Soft Polymers for Building up Small and Smallest Blood Supplying Systems by Stereolithography. Journal of Functional Biomaterials 3, no. 2 (March 29, 2012): 257–68. doi:10.3390/jfb3020257.
  • Novosel, E.; Meyer, W.; Klechowitz, N.; Krüger, H.; Wegener, M.; Walles, H.; Tovar, G.; Hirth, T.; Kluger, P.
    Evaluation of Cell‐Material Interactions on Newly Designed, Printable Polymers for Tissue Engineering Applications.
    Advanced Engineering Materials. Accessed November 28, 2011. doi:10.1002/adem.201180018.

Projects#

  • »BioRap – Herstellung bio-inspirierter Versorgungssysteme für Transplantate mittels Rapid Prototyping über Inkjet-Druck und Multiphotonenpolymerisation« (funded by Fraunhofer Gesellschaft, 2008 - 2011)
  • »ArtiVasc 3D – Artificial vascularised scaffolds for 3D-tissue regeneration« (funded by the EU, 2011 - 2015)
  • Fraunhofer-Leitprojekt »Theranostische Implantate: Biokompatible Implantatoberfläche durch 3D Druck von Biomolekülen und Stützstrukturen – Entwicklung gewebekompatibler Oberflächenausrüstung« (funded by Fraunhofer Gesellschaft, 2014 - 2018)