EAC Group

In the ElectroActive Coatings group we work to employ conducting polymers such as PEDOT and PPy for the purpose of developing multifunctional electrodes for neural recording and stimulation. Thanks to these materials sophisticated features, such as controlled delivery, can be implemented with high precision and controllability into a coating thinner than a micron. The devices carrying these coated electrodes can still be ultra-thin and flexible and retain excellent properties for recording and stimulation. Electroactive coatings are powerful for extending the functionalities of existing neuroelectronic research tools without sacrificing their overall performance.


  • Maria Asplund to receive funding by Brigitte-Schlieben-Lange-Programm, press release
  • A new paper from the group has been published in Biomaterials in March 2017, press release
  • Two papers have been published in the last quarter of 2016, one in ACS Applied Materials & Interfaces, one in IEEE Transactions on Neural Systems and Rehabilitation Engineering.

Research in the EAC Lab

In the lab we use various processes for our conducting polymer depositions.

The main technique is electrodeposition since it provides well adherent coatings with excellent properties for charge transfer over the solid-liquid boundary. Hence, the coated microelectrode obtains very low impedance in comparison to the bare metallic surface.

Furthermore, electrochemically driven deposition is limited to the conducting surfaces of the probe. Thus, such coatings can be applied subsequent to the final step of the probe microfabrication and there is no need for additional patterning.

In addition, we employ polymerization techniques such as vapor phase polymerization (VPP) for efficiently coating larger non-conducting substrates. Furthermore, casting of various PEDOT dispersion are used for rapid production of thick coatings.

Various electrochemical standard techniques are used to characterize the performance of our microelectrode coatings, thereamong:

  • Electrochemical impedance spectroscopy (EIS) 
  • Stress/stability testing via bi-phasic pulsing Cyclic voltammetry

Drug release is analyzed using

  • High Performance Liquid Chromatography (HPLC) 
  • Electrochemical Quartz Crystal Microbalance (EQCM) analysis 
  • Fluorometry

Morphology is analyzed using

  • SEM.

Although we have nothing specific listed at the moment you can always l send us your application for a M.Sc. project.


  • C. Boehler, C. Kleber, N. Martini, Y. Xie, I. Dryg, T. Stieglitz, U.G. Hofmann, M. Asplund, "Actively controlled release of Dexamethasone from neural microelectrodes in a chronic in vivo study", Biomaterials 129, 2017, 1-23. >LINK<

  • S. Heizmann, A. Kilias, P. Ruther, U. Egert, M. Asplund, "Active Control of Dye Release for Neuronal Tracing using PEDOT-PSS Coated Electrodes", IEEE Trans Neural Syst Rehabil Eng, 2016, 1-9. >LINK<

  • C. Boehler, F. Oberüber, S. Schlabach, T. Stieglitz, M. Asplund, "Long-term stable adhesion for conducting polymers in biomedical applications: IrOx and nanostructured platinum solve the chronic challenge", ACS Applied Materials & Interfaces, 2016, 1-18. >LINK<

  • C. Boehler, F. Güder, U. M. Kücükbayrak, M. Zacharias, and M. Asplund, "A Simple Approach for Molecular Controlled Release based on Atomic Layer Deposition Hybridized Organic-Inorganic Layers," Scientific Reports, vol. 6, p. 19574, 01/21/online 2016. >LINK<

  • A. Schopf, C. Boehler, M. Asplund, "Analytical methods to determine electrochemical factors in electrotaxis setups and their implications for experimental design", Bioelectrochemistry 2015;109:41-8. >LINK<

  • M. Asplund, "Degradable conjugated conducting polymers and nerve guidance", book chapter in Biosynthetic Polymers for Medical Applications, 1st Edition, Ed. by Poole-Warren, Martens and Green, Woodhead Publishing, 2015, ISBN: 9781782421054. >LINK<

  • C. Boehler, T. Stieglitz, M. Asplund "Nanostructured platinum grass enables superior impedance reduction for neural microelectrodes.", 2015, Biomaterials, 67 (346-353). >LINK<

  • A. Schopf, C. Boehler, M. Asplund, "Optical pH Surveillance in a Microfluidic System for Cell Culture", Application Note, PreSens precision sensing, 2015. >LINK<

  • S. Heizmann, A. Kilias, S. Okujeni, C. Boehler, P. Ruther, U. Egert and M. Asplund, “Accurate neuronal tracing of microelectrodes based on PEDOT-dye coatings”,  7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, Montpellier. DOI: 10.1109/NER.2015.7146640. >LINK<

  • C. Boehler, F. Oberueber, T. Stieglitz, and M. Asplund, „Iridium Oxide (IrOx) serves as adhesion promoter for conducting polymers on neural microelectrodes”, 7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, Montpellier. DOI: 10.1109/NER.2015.7146646. >LINK<

  • C. Boehler, M. Asplund, "A detailed insight into drug delivery from PEDOT based on analyticalmethods: Effects and side effects." J Biomed Mater Res Part A 2014:00A:000–000. >LINK<

  • M. Asplund, C. Boehler, T. Stieglitz, "Anti-inflammatory polymer electrodes for glial scar treatment." Frontiers in Neuroengineering, 7, 10.3389/fneng.2014.00009. >LINK<

  • M. Asplund, T. Nyberg, et al., "Electroactive polymers for neural interfaces." Polym. Chem., 1(9), 2010: 1374-1391. DOI:10.1039/C0PY00077A. >LINK<

  • E. M. Thaning, M. Asplund, et al., "Stability of poly(3,4-ethylene dioxythiophene) materials intended for implants." Journal of biomedical materials research. Part B, Applied biomaterials, 93(2), 2010: 407-415. >LINK<

  • M. Asplund, M. Nilsson, et al., "Incidence of traumatic peripheral nerve injuries and amputations in Sweden between 1998 and 2006." Neuroepidemiology, 32(3), 2009: 217-228. DOI:10.1159/000197900. >LINK<

  • M. Asplund, E. Thaning, et al., "Toxicity evaluation of PEDOT/biomolecular composites intended for neural communication electrodes." Biomedical materials, 4(4), 2009: 045009. >LINK<

  • M. Asplund, H. von Holst, et al., "Composite biomolecule/PEDOT materials for neural electrodes." Biointerphases, 3(3), 2008: 83-93. >LINK<

Group members

Dr. Maria Asplund (Group leader)
Tel: 0761/203 67375, Room: 102 00 83

Christian Böhler (PhD student)
Tel: 0761/203 67375, Room: 102 00 83

Stefanie Heizmann (PhD student)
Tel: 0761/203 98596, Room: 071 00-03.2

Carolin Kleber (PhD student)
Tel: 0761/203 98595, Room: 071 00-03.2

Anika Schopf (Technical Support)
Tel: 0761/203 67962, Room: 071 00-03.1

Felix Oberüber (HiWi)
Room: 102 00 40

Jean Chammas (HiWi)
Room: 102 00 40

Dunia Abed el Hafez (HiWi)
Room: 102 00 60