Bacterial survival in evaporating deposited droplets on a teflon-coated surface

Appl Microbiol Biotechnol. 2006 Dec;73(3):703-12. doi: 10.1007/s00253-006-0492-5. Epub 2006 Oct 20.

Abstract

Understanding of bacterial survival in aerosols is crucial for controlling infection transmission via airborne aerosols and/or large droplets routes. The cell viability changes of four bacteria species (Escherichia coli K12 JM109; Acinetobacter sp. 5A5; Pseudomonas oleovorans X5; and Staphylococcus aureus X8), three Gram-negative and one Gram-positive, in a large evaporating droplet of size 1,800 microm in diameter on teflon-coated slides were measured using the LIVE/DEAD BacLight solution and a microscope. Droplets of three levels of salinity (0, 0.9, and 36% w/v) were tested. All four species survived well during the droplet evaporation process, but died mostly at the time when droplets were dried out at 40-45 min. The final bacteria survival rate after droplets were completely dried was dependent on bacteria species and the salinity of the suspension solution. Droplet evaporation over the first 35-40 min had no adverse effect on bacterial survival for the droplets tested. The lethal effect of desiccation was found to be the most important death mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter / physiology
  • Aerosols
  • Bacteria
  • Bacterial Physiological Phenomena*
  • Colony Count, Microbial
  • Desiccation
  • Escherichia coli / physiology
  • Kinetics
  • Microbial Viability*
  • Models, Biological
  • Polytetrafluoroethylene*
  • Sodium Chloride / chemistry*
  • Staphylococcus aureus / physiology
  • Surface Properties
  • Water / chemistry
  • Water Microbiology*

Substances

  • Aerosols
  • Water
  • Sodium Chloride
  • Polytetrafluoroethylene