Journal of Materials Science: Materials in Medicine

, Volume 21, Issue 9, pp 2637–2651 | Cite as

Functionalization of electrospun fibers of poly(ε-caprolactone) with star shaped NCO-poly(ethylene glycol)-stat-poly(propylene glycol) for neuronal cell guidance

  • Kristina Klinkhammer
  • Julia Bockelmann
  • Chariklia Simitzis
  • Gary A. Brook
  • Dirk Grafahrend
  • Jürgen Groll
  • Martin Möller
  • Jörg Mey
  • Doris KleeEmail author


Microfibers produced with electrospinning have recently been used in tissue engineering. In the development of artificial implants for nerve regeneration they are of particular interest as guidance structures for cell migration and axonal growth. Using electrospinning we produced parallel-orientated biocompatible fibers in the submicron range consisting of poly(ε-caprolactone) (PCL) and star shaped NCO-poly(ethylene glycol)-stat-poly(propylene glycol) (sPEG). Addition of the bioactive peptide sequence glycine-arginine-glycine-aspartate-serine (GRGDS) or the extracellular matrix protein fibronectin to the electrospinning solution resulted in functionalized fibers. Surface characteristics and biological properties of functionalized and non-functionalised fibers were investigated. Polymer solutions and electrospinning process parameters were varied to obtain high quality orientated fibers. A polymer mixture containing high molecular weight PCL, PCL-diol, and sPEG permitted a chemical reaction between hydroxyl groups of the diol and isocyanante groups of the sPEG. Surface analysis demonstrated that sPEG at the fiber surface minimized protein adhesion. In vitro experiments using dorsal root ganglia explants showed that the cell repellent property of pure PCL/sPEG fibers was overcome by functionalization either with GRGDS peptide or fibronectin. In this way cell migration and axonal outgrowth along fibers were significantly increased. Thus, functionalized electrospun PCL/sPEG fibers, while preventing non-specific protein adsorption, are a suitable substrate for biological and medical applications.


Dorsal Root Ganglion Schwann Cell Protein Adsorption Electrospun Fiber Nerve Conduit 
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.



Bovine serum albumin


4,6-Diamidino-2-phenylindole dihydrochloride




Days in vitro


Dulbecco’s modified eagle medium


Dimethyl sulfoxide


Dorsal root ganglia


Extracellular matrix


Fetal calf serum


One letter code of the peptide sequence GlyArgGlyAspSer


Molecular weight


Neurofilament 200 kDa


Normal goat serum




Phosphate buffer saline




PCL diol


Poly(ethylene glycol)


Peripheral nervous system


Protein antibody, marker for Schwann cells


Schwann cells


Scanning electron microscopy


Star shaped NCO-poly(ethylene glycol)-stat-poly(propylene glycol)




Tris-buffered saline with 1% Triton-X 100


Weight percent


X-ray photoelectron spectroscopy



We thank Marie Pradella for help with evaluating the cell experiments. Kristin Michael and Bernd Hoffmann kindly allowed us to use their equipment for making composite photographs of DRG explants. This work was supported by a grant from the Interdisciplinary Centre for Clinical Research “BIOMAT” within the faculty of Medicine at Aachen University (RWTH) (TV B111) and by DFG-Graduiertenkolleg 1035 “Biointerface”. Julia Bockelmann was supported by a Marie-Curie EST grant from the EU (EURON).


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Kristina Klinkhammer
    • 1
  • Julia Bockelmann
    • 2
    • 3
  • Chariklia Simitzis
    • 1
  • Gary A. Brook
    • 4
    • 5
  • Dirk Grafahrend
    • 1
  • Jürgen Groll
    • 1
  • Martin Möller
    • 1
  • Jörg Mey
    • 2
    • 3
  • Doris Klee
    • 1
    Email author
  1. 1.Institute of Technical and Macromolecular Chemistry and DWI e.V.RWTH Aachen UniversityAachenGermany
  2. 2.Institute of Biology IIRWTH Aachen UniversityAachenGermany
  3. 3.EURON Graduate School of NeuroscienceMaastrichtNetherlands
  4. 4.Institute of Neuropathology, Medical FacultyRWTH Aachen UniversityAachenGermany
  5. 5.IZKF-BIOMAT, Aachen University Hospital, RWTH Aachen UniversityAachenGermany

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