Patent ID: 8173416

Claim:
A circuit arrangement for introducing nucleic acids, peptides, proteins and/or other biologically active molecules into the cell nucleus of eukaryotic cells by means of electric current or for the treatment of cells, cell derivatives, subcellular particles and/or vesicles with electric current, the circuit arrangement comprising: a first storage device for electrical charge; a first high-voltage power supply configured to supply the first storage device; a first power semiconductor configured to transfer a first quantity of charge of the first storage device into a suspension in a cuvette; a second storage device for electrical charge; a second high-voltage power supply configured to supply the second storage device; a second power semiconductor configured to transfer a second quantity of charge of the second storage device into the suspension in the cuvette; a current regulating unit coupled to the second semiconductor and configured to regulate charge transferred to the cuvette through the second power semiconductor; and a control device for controlling the first power semiconductor and for controlling the second power semiconductor with the current regulating unit so as to: charge the first storage device with a preset voltage (U1) and the second storage device with a voltage U2=R×I2×K2, where R is a resistance of the cuvette and the suspension therein, I2 is a desired current and K2 is a correction value which takes into account a property of the cuvette; and transfer a first pulse with the voltage (U1) of the first storage device to the cuvette for a preset time; wherein the control device is configured to determine a delivered quantity of charge in at least one selectable time interval, to compare a preset desired quantity of charge with the delivered quantity of charge, and to block at least one of the first and second power semiconductors on a reaching or exceeding of the desired quantity of charge.