A Novel and Flexible Microplasma Discharge Device for Inactivating Pathogens Suspended in Fluids

A flexible microplasma discharge device (MDD) was successfully developed for inactivating a gram-negative pathogenic bacterium, Pseudomonas aeruginosa, under ambient operating conditions. The MDD was fabricated by sandwiching a flexible polyethylene terephthalate (PET) film as the dielectric layer, between copper based top and bottom electrodes. The top and bottom electrodes, which consists of copper tapes were patterned in a honeycomb and circular design respectively, using laser ablation. The efficacy of the MDD to inactivate P. aeruginosa cells in phosphate buffer saline (PBS) was investigated by testing the effect of varying treatment times ranging from 1 minute to 10 minutes. An 8log10 reduction in bacterial viability was achieved when the MDD was activated for 8.5 minutes at an input voltage of 10 V. The flexibility of the device was also tested by bending the MDD on surfaces with a radius of curvature of 25 mm and 50 mm. The calculated power density of the MDD in bent condition was compared with the power density in its unbent state. The performance of the MDD is analyzed and presented in this paper.