Dexamethasone electrically controlled release from polypyrrole-coated nanostructured electrodes

  • Lucas Leprince
  • Audrey Dogimont
  • Delphine Magnin
  • Sophie Demoustier-ChampagneEmail author


One of the key challenges to engineering neural interfaces is to reduce their immune response toward implanted electrodes. One potential approach to minimize or eliminate this undesired early inflammatory tissue reaction and to maintain signal transmission quality over time is the delivery of anti-inflammatory biomolecules in the vicinity of the implant. Here, we report on a facile and reproducible method for the fabrication of high surface area nanostructured electrodes coated with an electroactive polymer, polypyrrole (PPy) that can be used to precisely release drug by applying an electrical stimuli. The method consists of the electropolymerization of PPy incorporated with drug, dexamethasone (DEX), onto a brush of metallic nanopillars, obtained by electrodeposition of the metal within the nanopores of gold-coated polycarbonate template. The study of the release of DEX triggered by electrochemical stimuli indicates that the system is a true electrically controlled release system. Moreover, it appears that the presence of metallic nanowires onto the electrode surface improves the adherence between the polymer and the electrode and increases the electroactivity of the PPy coating.


Cyclic Voltammetry Pore Density Control Release System Nanostructured Electrode Pillar Height 
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.



The authors thank Etienne Ferain and it4ip company for supplying polycarbonate membranes. L. L. acknowledges the financial support provided by the FNRS-FRIA. S.D.-C also thanks the F.R.S-FNRS for her Senior Research Associate position. The work was partly supported by the Wallonia Region (BIOWIN program, DEEP project).


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Lucas Leprince
    • 1
  • Audrey Dogimont
    • 1
  • Delphine Magnin
    • 1
  • Sophie Demoustier-Champagne
    • 1
    Email author
  1. 1.Unité de Chimie et de Physique des Hauts PolymèresUniversité catholique de LouvainLouvain-la-NeuveBelgium

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