Development of Flexible Microplasma Discharge Device for Sterilization Applications

A flexible microplasma discharge device (MDD) was successfully developed for sterilization of Pseudomonas aeruginosa, a gram-negative bacterium, using ambient air as the sterilizing agent. The MDD was fabricated by sandwiching a flexible polyethylene terephthalate (PET) film, as the dielectric layer, between two layers of flexible copper tape, as top and bottom electrodes. The copper tape was patterned in a honeycomb and circular design for the top and bottom electrodes, respectively, using laser ablation. The sterilizing capability of the MDD was investigated by testing the effect of varying parameters including gap distance (1 mm to 9 mm) and treatment time (10 seconds to 300 seconds) for the sterilization of P. aeruginosa. A sterilization efficacy of 100% was achieved for gap distances ranging from 1 mm to 9 mm, when compared to the control. In addition, sterilization efficacies of 99.9% and 100% was achieved with a treatment time of 10 seconds and 60 seconds, respectively. Surface temperatures ranging from 26.2 °C to 72.8 °C were observed as the input voltage was increased from 4 V to 10.5 V, respectively. The performance of the MDD is analyzed and presented in this paper.