Aukšto dažnio stačiakampių impulsų elektroporacijos sistemos kūrimas ir tyrimas

The dissertation provides the research and development of the high-frequency square wave pulse electroporation system and proposes a topolgy of planar electroporation electrodes for real-time electroporation applications. An analysis and applied research of the electrical pulse forming circuits, the electric field generation technologies and the compensation circuits for high-frequency transient as well as the electric field distribution of planar electroporation electrodes are carried out. The introductory chapter deals with the problem of the thesis, research goals and newness, describes the research methodology and defended statements. The first chapter presents the most relevant scientific literature related to the main subjects of this dissertation. The electroporation phenomena and the dependence of the cell response on electrical pulses duration and frequency are presented. The review of submicrosecond and nanosecond electric pulse generators and high-frequency transient process compensation circuits are also presented. This Chapter concludes in formulating tasks the dissertation. The second chapter presents simulation models of the high-voltage, high-frequency submicrosecond pulsed electric field (nsPEF) generator and planar electrodes for real-time electroporation. The SPICE model of pulse forming circuit is developed and the effects of the parasitic circuit elements and transient processes to the generated electric pulse are investigated. The chapter includes the potential applications and needs of the planar electrodes for electroporation. The topology of planar electrodes and its influence on electric field homogeneity are analysed using finite element method (FEM) in COMSOL Multiphysics environment. The third chapter presents the research and development of novel high-frequency square-wave electroporation system. The developed system can produce single and bursts deliver adjustable square-wave electric pulses with load independent pulse fall time. The pulse amplitude, repetition frequency and pulse duration can be adjusted accordingly up to 3 kV, from 1 Hz to 3.5 MHz and from 100 ns to 1 ms. In this chapter, the system simulation and the experimental results are compared. The prototype system is successfully tested for the inactivation of the human pathogen Candida albicans. The main results of the thesis were published in 6 scientific articles: three – in scientific journals included in Clarivate Analytics Web of Science database with impact factor, two – in international conference publications which are referred by Clarivate Analytics Web of Science database Proceedings, one article is printed in peer-reviewed scientific journal listed in Index Copernicus database. The research results were presented in 10 scientific conferences.Doctoral dissertatio