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Gewählte Doctoral Thesis:

Terje Wimberger (2020): High-k passivated electrodes: On the electrodynamic behavior of cells under the influence of capacitively coupled electric fields.
Doctoral Thesis - Institut für Synthetische Bioarchitekturen, BOKU-Universität für Bodenkultur, pp 58. UB BOKU obvsg FullText

Data Source: ZID Abstracts
Most students of biology have come across electroporation at least once when performing genetic manipulation of bacteria in a basic lab course; Mix the bacterial suspension with foreign DNA in a cuvette with flanking electrodes, press the magic button and extract genetically modified bacteria from a foamy solution. Incredible. How does this work and why? Electroporation refers to the manipulation of living cells by electric fields. The outer membrane of these cells will undergo dielectric breakdown when exposed to an externally applied electric field of sufficient magnitude. This manifests in the creation of pores through which otherwise confined molecules can enter or leave the cell - hence the term electroporation. When we press the magic button, we are inevitably transferring electrical energy to the solution where it is converted to thermal and chemical energy. The latter consists of pH change and bubble formation causing the visual feedback. The problem with changes in temperature and these types of chemical processes is that their biological impact cannot be controlled, meaning they introduce a significant chaos-factor into the equation. The outcome of a single delivery event will at least depend on local field strength, temperature, pH and the vicinity to a gas bubble - all of which are time-varying parameters. Sound complicated? Precisely is not a suitable term in this context. The amount of dead and successfully manipulated cells won’t square up between multiple repetitions, resulting in a highly frustrating user experience. The technological advancement presented in this thesis is a removal of the chaos factor by what we term high-k dielectric electrode passivation. This results in capacitive coupling, essentially describing an electric field application where the transformation of electrical energy into its detrimental forms, like thermal and chemical energy, is significantly reduced.

Betreuer: Ehmoser Eva-Kathrin
1. Berater: Kasper Cornelia
2. Berater: Oostenbrink Chris

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