Development of pulse generators and electrodes for cell electroporation

Matej Reberšek, University of Ljubljana

Abstract:

Electroporation of cells is being successfully used in biology, biotechnology and medicine. However for successful and wide use of electroporation based technologies and treatments adequate pulse generators and electrodes need to be available[1]. For example electrochemotherapy and non-thermal irreversible electroporation, which are based on cell membrane electroporation, cannot be performed without a specific device, namely an electroporator. Also in biotechnology, the electroporation is already used for liquid food sterilization, water treatment and extraction of substances from microorganisms and plants. The electroporator delivers short high-voltage pulses to the target tissue efficiently and safely for the patient and operator, and is compatible to other devices. The pulse generator generates electric pulses of specific shape, amplitude, duration, number and repetition frequency [2] and electrodes deliver electric pulses to target cells (i.e. the load) [1]. The energy that is provided to the load is governed by the number of pulses, and the pulse voltage, current and duration. The energy of the electroporation pulses in biomedical applications can reach several joules whereas in biotechnology where electroporation is used for treatment of agriculture products and water the energy of the electroporation pulses can reach several kilojoules. Such a large energy of the electroporation pulses is needed in biotechnology including food processing when a large amount of medium is processed by electroporation also termed as pulsed electric field (PEF) treatment.

            Cell membrane electroporation enables specific biomedical or biotechnological application. To achieve this goal appropriate electroporation protocol needs to be followed. The diversity of the electroporation applications and the range of the targeted loads have led to numerous electroporation protocols and at the same time to the development of many different electrodes and pulse generators[3]. In general electrodes can be divided according to targeted load namely cell suspension or tissue, and pulse generators can be divided according to purpose of use namely laboratory, clinical or industrial electroporators. Pulse generators, within their capacity, control the voltage, the current or the energy of the output signal. However, all three given parameters are interrelated and depend on the impedance of the load which is determined by the geometry, the resistivity and permittivity of the load.

[1]       M. Reberšek, C. Bertacchini, M. Sack, and D. Miklavcic, “Cell Membrane Electroporation – Part 3: The Equipment,” IEEE Electrical Insulation Magazine, Submitted.

[2]       M. Reberšek and D. Miklavcic, “Advantages and Disadvantages of Different Concepts of Electroporation Pulse Generation,” Automatica, vol. 52, no. 1, pp. 12–19, Mar. 2011.

[3]       M. Reberšek and D. Miklavcic, “Concepts of Electroporation Pulse Generation and Overview of Electric Pulse Generators for Cell and Tissue Electroporation,” in Advanced Electroporation Techniques in Biology and Medicine, A. G. Pakhomov, D. Miklavcic, and M. S. Markov, Eds. Boca Raton: CRC Press, 2010, pp. 323–339.