This title appears in the Scientific Report : 2002 

Extrazelluläre Signalableitung von Kardiomyozyten und genetisch modifizierten HEK 293-Zellen mit Feldeffekttransistoren und Mikroelektrodenarrays
Ecken, Holger (Corresponding author)
Institut für Bio- und Chemosensoren; ISG-2
Jülich Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag 2002
127 p.
Essen, Univ., Diss., 2002
Dissertation / PhD Thesis
Materialien, Prozesse und Bauelemente für die Mikro- und Nanoelektronik
Berichte des Forschungszentrums Jülich 4019
Please use the identifier: in citations.
The focus of this work was to investigate the bioelectronic interface between electrically active cells and microelectrode arrays or field-effect transistors. Therefore a successful coupling of the cells to the transducer systems, sufficiently sensitive measuring systems and a suitable experimental setup were necessary. For the analysis of the bioelectronic interface an electrophysiological setup was constructed and extended with an extracellular measuring system. This setup offers the possibility to analyze intra- and extracellular signals from cells at the same time. As cell systems, primarily cultured cardiac myocytes (heart muscle cells) of embryonic rats and the human embryonic kidney cell line HEK 293 were used. After approximately 2-4 days the cardiac myocytes formed "in vitro" a confluent cell layer (Syncytium), which showed spontaneous contractions. For the analysis of the signal distribution within such a cellular network, microelectrode arrays with 64 gold microelectrodes were fabricated using silicon planar technology. An already available measuring system for the microelectrodes was extended to 64 channels. To investigate the extracellular coupling of individual cells, single cell experiments were performed using genetically modified HEK 293-cells and field-effect transistors. The cells were modified by a stable transfection of a gene, coding for K$^{+}$-selektive ion channels. In this way the influence of K$^{+}$-ionic currents to the resulting extracellular signals has been specifically investigated. lt was found out that the different temporal influx of K$^{+}$-ions into the contact area between cell and field-effect transistor clearly affects the extracellular coupling.