Development of a standardized and safe airborne antibacterial assay, and its evaluation on antibacterial biomimetic model surfaces

PLoS One. 2014 Oct 31;9(10):e111357. doi: 10.1371/journal.pone.0111357. eCollection 2014.

Abstract

Bacterial infection of biomaterials is a major concern in medicine, and different kinds of antimicrobial biomaterial have been developed to deal with this problem. To test the antimicrobial performance of these biomaterials, the airborne bacterial assay is used, which involves the formation of biohazardous bacterial aerosols. We here describe a new experimental set-up which allows safe handling of such pathogenic aerosols, and standardizes critical parameters of this otherwise intractable and strongly user-dependent assay. With this new method, reproducible, thorough antimicrobial data (number of colony forming units and live-dead-stain) was obtained. Poly(oxonorbornene)-based Synthetic Mimics of Antimicrobial Peptides (SMAMPs) were used as antimicrobial test samples. The assay was able to differentiate even between subtle sample differences, such as different sample thicknesses. With this new set-up, the airborne bacterial assay was thus established as a useful, reliable, and realistic experimental method to simulate the contamination of biomaterials with bacteria, for example in an intraoperative setting.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerosols*
  • Anti-Bacterial Agents / pharmacology*
  • Biological Assay / standards*
  • Biomimetic Materials / pharmacology*
  • Microbial Sensitivity Tests / standards*
  • Reference Standards
  • Safety*
  • Surface Properties

Substances

  • Aerosols
  • Anti-Bacterial Agents

Grants and funding

This study was supported by the Freiburg Institute for Advanced Studies (FRIAS) and the German Research Foundation (DFG, LI 1714/5-1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.