Development and characterization of a coronary polylactic acid stent prototype generated by selective laser melting

  • Christian Flege
  • Felix Vogt
  • Simon Höges
  • Lucas Jauer
  • Mauricio Borinski
  • Vera A. Schulte
  • Rainer Hoffmann
  • Reinhart Poprawe
  • Wilhelm Meiners
  • Monika Jobmann
  • Konrad Wissenbach
  • Rüdiger Blindt


In-stent restenosis is still an important issue and stent thrombosis is an unresolved risk after coronary intervention. Biodegradable stents would provide initial scaffolding of the stenosed segment and disappear subsequently. The additive manufacturing technology Selective Laser Melting (SLM) enables rapid, parallel, and raw material saving generation of complex 3- dimensional structures with extensive geometric freedom and is currently in use in orthopedic or dental applications. Here, SLM process parameters were adapted for poly-l-lactid acid (PLLA) and PLLA-co-poly-ε-caprolactone (PCL) powders to generate degradable coronary stent prototypes. Biocompatibility of both polymers was evidenced by assessment of cell morphology and of metabolic and adhesive activity at direct and indirect contact with human coronary artery smooth muscle cells, umbilical vein endothelial cells, and endothelial progenitor cells. γ-sterilization was demonstrated to guarantee safety of SLM-processed parts. From PLLA and PCL, stent prototypes were successfully generated and post-processing by spray- and dip-coating proved to thoroughly smoothen stent surfaces. In conclusion, for the first time, biodegradable polymers and the SLM technique were combined for the manufacturing of customized biodegradable coronary artery stent prototypes. SLM is advocated for the development of biodegradable coronary PLLA and PCL stents, potentially optimized for future bifurcation applications.


PLLA Drug Elute Stents Selective Laser Melting Coronary Artery Stents Selective Laser Melting Process 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) within the Sonderforschungsbereich Transregio 37 (Mikro- und Nanosysteme in der Medizin). We would like to thank Dipl. Ing. Dieter Jacobi, University Duisburg Essen, for his technical support regarding gel permeation chromatography.


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Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Christian Flege
    • 1
  • Felix Vogt
    • 1
  • Simon Höges
    • 2
  • Lucas Jauer
    • 2
  • Mauricio Borinski
    • 1
  • Vera A. Schulte
    • 3
  • Rainer Hoffmann
    • 1
  • Reinhart Poprawe
    • 2
    • 4
  • Wilhelm Meiners
    • 4
  • Monika Jobmann
    • 5
  • Konrad Wissenbach
    • 4
  • Rüdiger Blindt
    • 1
  1. 1.Department of CardiologyRWTH Aachen UniversityAachenGermany
  2. 2.Department of Laser Technology LLTRWTH Aachen UniversityAachenGermany
  3. 3.Deutsches Wollforschungsinstitut at the RWTH Aachen UniversityAachenGermany
  4. 4.Fraunhofer Institute for Laser Technology ILTAachenGermany
  5. 5.Fraunhofer Institute for Applied Polymer Research IAPPotsdamGermany

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