Figure 1.

(a) The in vitro sonoporation apparatus comprised an immersed, sealed treatment cartridge, placed a fixed distance from the ultrasonic transducer. (b) The chamber volume was 0.2 mL, with a total transverse internal width of 2.5 mm. Placement of acoustically transparent polystyrene windows (0.1-mm thick, ~2% reduction in PNP) on the front and back of the chamber allowed ultrasound to travel through with minimal reflections, and a 2-mm magnetic stir bar maintained constant fluid flow in the chamber.