Sterilization of Spores Using a Direct Current Steady State Atmospheric Pressure Plasma Discharge Apparatus

Summary form only given. The paper investigates the efficacy of the atmospheric pressure plasma discharge apparatus in sterilization of spores. The plasma sterilizer was tested on a highly resistant spore producing bacterial strain Geobacillus stearothermophilitis. This particular strain is commonly used in biological indicator strips used to monitor autoclaves and steam sterilizers. The experimental strategies employed include agar plate inoculation, biological indicators, and microscopic evaluation. Tests were also conducted wherein the spores were exposed to an atmospheric pressure plasma discharge in a hydrogen peroxide (30%) environment. Preliminary test results showed 90-100% kill rate (CFU counts) within the range of 3-5 minutes of exposure intervals. The experimental findings are in good agreement with earlier tests conducted on Escherichia coli and Wild type standard Lambdaphage using the same device. The test results in essence establish the effectiveness of the sterilizer across different classes of microorganisms. The portability, ruggedness, versatility of the plasma discharge apparatus (Dual power operability-AC/DC) and reliable sterilization efficiency renders it practical and functional even in remote warfare milieu.