Modification of cells by introduction of exogenous material

A method of electroporating cells comprising:

• providing an FTEP device comprising:
• 1) an inlet reservoir, an inlet, and an inlet channel for receiving a fluid comprising cells and exogenous material into the FTEP device, wherein the inlet reservoir originates from the top surface of the FTEP device;
• 2) an outlet reservoir, an outlet, and an outlet channel for removing a fluid comprising transformed cells and exogenous material from the FTEP device, wherein the outlet reservoir originates from the top surface of the FTEP device;
• 3) a flow channel positioned between the inlet and outlet channels where the flow channel decreases in width between the point where the inlet channel enters the flow channel and the outlet channel exits the flow channel;
• 4) a first electrode and a second electrode wherein the two electrodes form a portion of a wall of the flow channel where the flow channel decreases in width, and wherein the electrodes apply one or more electric pulses to the cells in the fluid as they pass through the flow channel, thereby introducing exogenous material into the cells in the fluid;
• and a pressure source, 5) a flow sensor measurement device and a processor wherein according to the processor, the pressure source pushes flow of the cells and exogenous material between the inlet reservoir and the outlet reservoir, the flow sensor measurement device senses flow of the cells and exogenous material and, when the flow sensor measurement device detects an increase in air flow indicative of fluid being completely drained from the inlet reservoir, the flow sensor measurement device communicates with the processor to communicate with the pressure source to pull flow of the cells and exogenous material between the outlet reservoir and the inlet reservoir, thereby reversing the flow of the cells and exogenous material;
• pulling the cells and exogenous material into the inlet reservoir, inlet, inlet channel, flow channel, and past the two electrodes;
• providing electrical pulses to the cells as the cells are pulled through the flow channel past the electrodes producing electroporated cells;
• collecting the electroporated cells in the outlet reservoir;
• detecting an increase in air flow indicative of fluid being drained from the inlet reservoir;
• reversing pressure to push the electroporated cells through the outlet reservoir, outlet, outlet channel, flow channel and past the two electrodes;
• providing electrical pulses to the cells as the cells are pushed through the flow channel past the electrodes producing twice-electroporated cells;
• and
• collecting the twice-electroporated cells in the inlet reservoir.