A Novel Method for Fabricating Microfluidic Devices Containing Immobilized Biological Specimens

  • Medina Hamidovic

    Institute for Communications Engineering and RF-Systems, Johannes Kepler University Linz, Altenbergerstraße 69, 4040 Linz, Austria

  • Ferenc Ender

    Department of Electron Devices, Faculty of Electrical Engineering and Informatics, Budapest University of Technology and Economics, H-1117 Budapest, P.O. Box 91, Hungary


Microfluidic devices are dominantly fabricated using the soft lithography microfabrication techniques and polydimethylsiloxane (PDMS) as a structural material. Although the technique is applicable for the majority of microfluidic devices, it has limited use for the fabrication of microfluidic devices with immobilized biological specimen due to the low biocompatibility- a consequence of the plasma-assisted bonding step during the assembly of the final device. In this step, biological specimens within the microfluidic device are affected by strong plasma exposure which ultimately can degrade their biochemical activity and stability. To the best of our knowledge, this paper presents for the first time a method for increasing the biocompatibility of a conventional PDMS soft lithography process and enables fabrication of the microfluidic devices containing immobilized biological specimens. Protection of the biological specimen during the plasma bonding step is ensured by placing a protective Polyvinyl Alcohol (PVA) nanofiber layer over the biological specimens. The method is verified against the conventional soft lithography method by fabricating microfluidic devices containing enzyme-filled microreactors and following enzymatic reactions. It was shown that inadvantageous impact of the plasma is reduced by utilizing a protective PVA layer which ultimately preserves the specific activity and biochemical stability of the immobilized enzymes.

Keywords: microfabrication, polydimethylsiloxane (PDMS), polyvinyl alcohol nanofiber, immobilization, microfluidic devices
Published online
How to Cite
Hamidovic, M., Ender, F. “A Novel Method for Fabricating Microfluidic Devices Containing Immobilized Biological Specimens”, Periodica Polytechnica Electrical Engineering and Computer Science, 63(2), pp. 85-93, 2019. https://doi.org/10.3311/PPee.13523