(526c) Sterilization of Bacteria by Pulsed Electric Field On Microfluidic Chip

High temperature heat sterilization technique has been widely used for the sterilization of water and foods due to its simplicity and high efficiency. However, this process is energy-intensive and the high temperature can adversely affect nutritional qualities and flavor of food. Some of the aforementioned shortcomings can be overcome by the pulsed electric field (PEF) sterilization technique, which is nonthermal and uses short-duration (tens of ns to 100 ms) high-field electric pulses to sterilize liquid foods such as fruit juices, beer, milk, and cream. However, due to large distance between the two counter electrodes used in the typical PEF systems, high-voltage pulses provided by an expensive high-voltage pulse generator are required to achieve high electric field. With the advancement of microfabrication technologies, high electric field pulses can be easily generated by a low-voltage pulse generator when the two counter electrodes are a few hundred micron meters apart. A microfluidic chip for sterilization of bacteria using the PEF sterilization technique has been designed and fabricated. The side walls of the microfluidic channel also serve as the two counter electrodes, which are 100 mm apart. The performance of the chip was tested by sterilization of Escherichia coli under various conditions.