Sterilization and Decontamination of Surfaces Contaminated With Biological and Chemical Warfare Agents Using Atmospheric Pressure Plasma Discharges

摘要

Our Phase I effort was meant to demonstrate that an effective technology for rapid surface sterilization of biological contaminants and neutralization of chemical warfare agents could be developed based on the application of an atmospheric pressure plasma. We used both a DC corona and dielectric barrier discharge for the sterilization tests which were conducted on a variety of substrates including metals and chemically resistant fabrics. Medically accepted biological indicator spores (Bacillus subtilis var niger and Bacillus stearothermophilus) were used to determine the effectiveness of the plasma discharge. The chemical neutralization tests were conducted using a DC corona discharge on a metal substrate contaminated with either diisopropylmethyl phosphonate or dimethylmethyl phosphonate. These simulants are of similar chemical structure to classes of chemical warfare agents like GB and Sarin. Results include decomposition of the chemical agent simulants with decomposition by-products including water, acetic acid and gases like CO2; complete sterilization in 15 minutes of some substrates contaminated with up to 105 spores over about a 1 cm2 and the concentration of the model pathogens and the surface characteristics of the contaminated substrate affects the sterilization results. A rough surface with defects is difficult to completely sterilize on short time scales.