Biofilm Remediation Using Cold Atmospheric Pressure Plasma Planar and Radial Arrays

Abstract

Cold Atmospheric-Pressure Plasma (CAP) planar and radial arrays have been developed to both inactivate and remove biofilms from surfaces [1] , [2] . The planar arrays are made from Low Temperature Co-fired Ceramic (LTCC), consisting of 8 linear discharge elements 2.4 cm long with a 0.75 mm gap between each element, and operate at 1-3 kV, 20 kHz AC. Typical gas flows use Ar at 13 SLM hydrated with water. Previous results show generation of hydrogen peroxide and hydroxyl radicals which increase linearly with plasma exposure times from the arrays and >99% Colony Forming Unit (CFU) reduction in <60 s for bacterial biofilms on a range of substrates (stainless steel, glass, plastic) [1] . Here we apply these arrays on a much larger surface area (10× 10 cm) by scanning the active array across a surface. The CFU count, chemical assays, and etch rates for this experiment will be presented. The radial arrays consist of four LTCC elements ≈3 cm in diameter with ≈0.75 cm gaps between each element. These radial arrays are designed for use in pipes. Imaging of biofilm removal is also under development.