Abstract
Flexible microplasma discharge devices (MDDs) were successfully developed for inactivation of gram-negative bacteria such as <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Escherichia coli</i> ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E. coli</i> ) and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Pseudomonas aeruginosa</i> ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P. aeruginosa</i> ), using ambient air as the sterilizing agent. The design of the electrodes influences the voltage distribution across the device and is an important contributor to the overall sterilization efficacy. Therefore, the voltage distribution across the top electrode of two different MDDs (designed in comb and honeycomb patterns) was analyzed initially using COMSOL Multiphysics simulation software. The honeycomb-patterned MDD resulted in a uniform distribution of the applied voltage as compared to the comb-structured MDD. The fabrication of MDD was realized using a flexible copper tape and polyethylene terephthalate (PET) film. Top electrodes of comb and honeycomb design were patterned using a laser ablation process. Similarly, rectangular and circular-shaped bottom electrodes were laser ablated for the comb and honeycomb-structured MDDs, respectively. PET was used as the dielectric layer, sandwiched between top and bottom layers of a flexible copper tape. The efficacy of the MDDs was analyzed by varying parameters, such as the gap distance between the MDD surface and bacteria (1–9 mm), treatment time (10–300 s), input dc voltage (4–8 V), and bacterial concentrations. Surface temperatures ranging from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\sim }26~{^\circ }\text{C}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\sim }33~{^\circ }\text{C}$ </tex-math></inline-formula> were observed as the input voltage was increased from 4 to 8 V, respectively, for both MDDs. It was observed that the honeycomb-patterned MDD inactivated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\sim }4$ </tex-math></inline-formula> Log <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sub> of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">E. coli</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P. aeruginosa</i> cells in less than 20 s as compared to two minutes for the comb-structured MDD for an input voltage of 10 V. Bacterial viability against varying parameters using comb and honeycomb-patterned MDDs was analyzed and is presented in this article.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: IEEE Transactions on Radiation and Plasma Medical Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
