Modification of cells by introduction of exogenous material

A method of electroporating cells comprising:

• providing a flow-through electroporation (FTEP) device, wherein the flow-through electroporation device comprises an inlet and at least an inlet channel for receiving a fluid comprising electrocompetent cells and exogenous material into the FTEP device;
• an outlet and an outlet channel for removing a fluid comprising transformed cells and exogenous material from the FTEP device;
• a flow channel intersecting and positioned between the inlet channel and the outlet channel, wherein the flow channel decreases in width to a dimension no smaller than at least 2× diameter of the cells being electroporated between the first inlet channel and a center of the flow channel and the outlet channel and the center of the flow channel;
• and two electrodes positioned between the intersection of the flow channel with the inlet channel and the intersection of the flow channel with the outlet channel;
• wherein the electrodes are in fluid and electrical communication with fluid in the flow channel but not directly in the path of the cells traveling through the flow channel;
• flowing the cells comprising the electrocompetent cells and exogenous material into the inlet and the inlet channel;
• flowing the cells through the flow channel and past the two electrodes;
• providing electrical pulses to the cells in the fluid as the cells flow through the flow channel past the electrodes producing electroporated cells;
• and
• removing the electroporated cells from the outlet channel and outlet.