Development of an aerosol surface inoculation method for bacillus spores

Appl Environ Microbiol. 2011 Mar;77(5):1638-45. doi: 10.1128/AEM.02237-10. Epub 2010 Dec 30.

Abstract

A method was developed to deposit Bacillus subtilis spores via aerosolization onto various surface materials for biological agent decontamination and detection studies. This new method uses an apparatus coupled with a metered dose inhaler to reproducibly deposit spores onto various surfaces. A metered dose inhaler was loaded with Bacillus subtilis spores, a surrogate for Bacillus anthracis. Five different material surfaces (aluminum, galvanized steel, wood, carpet, and painted wallboard paper) were tested using this spore deposition method. This aerosolization method deposited spores at a concentration of more than 10(7) CFU per coupon (18-mm diameter) with less than a 50% coefficient of variation, showing that the aerosolization method developed in this study can deposit reproducible numbers of spores onto various surface coupons. Scanning electron microscopy was used to probe the spore deposition patterns on test coupons. The deposition patterns observed following aerosol impaction were compared to those of liquid inoculation. A physical difference in the spore deposition patterns was observed to result from the two different methods. The spore deposition method developed in this study will help prepare spore coupons via aerosolization fast and reproducibly for bench top decontamination and detection studies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerosols*
  • Bacillus subtilis / isolation & purification*
  • Bacteriological Techniques / methods*
  • Environmental Microbiology*
  • Equipment Contamination*
  • Reproducibility of Results
  • Spores, Bacterial / isolation & purification*

Substances

  • Aerosols