Nitric oxide-releasing polyacrylonitrile disperses biofilms formed by wound-relevant pathogenic bacteria

J Appl Microbiol. 2016 Apr;120(4):1085-99. doi: 10.1111/jam.13059. Epub 2016 Mar 1.

Abstract

Aims: To test the antimicrobial and antibiofilm properties of a nitric oxide (NO)-releasing polymer against wound-relevant bacterial pathogens.

Methods and results: Using a variety of 96-well plate assay systems that include standard well plates and the minimum biofilm eradication concentration biofilm assay well plate, a NO-releasing polymer based on (poly)acrylonitrile (PAN/NO) was studied for antimicrobial and antibiofilm activity against the common wound pathogens Pseudomonas aeruginosa (PAO1), Staphylococcus aureus (Mu50) and Enterococcus faecalis (V583). The polymer was capable of dispersing single-species biofilms of Ps. aeruginosa as well as a more clinically relevant multispecies biofilm that incorporates Ps. aeruginosa along with Staph. aureus and Ent. faecalis. PAN/NO also synergistically enhanced the susceptibility of the multispecies biofilms to the common broad-spectrum antibiotic, ciprofloxacin. Multiple in vitro biocompatibility assays show that PAN/NO has limited potential for mammalian cytotoxicity.

Conclusion: This study demonstrates the feasibility of utilizing the NO-releasing polymer, PAN/NO, to manage biofilms formed by wound-relevant pathogens, and provides proof-of-concept for use of this NO-releasing polymer platform across multiple disciplines where bacterial biofilms pose significant problems.

Significance and impact of study: In the clinical sector, bacterial biofilms represent a substantial treatment challenge for health care professionals and are widely recognized as a key factor in prolonging patient morbidity. This study highlights the potential role for the ubiquitous signalling molecule nitric oxide (NO) as an antibiofilm therapy.

Keywords: biofilm; biofilm dispersal; chronic wounds; nitric oxide; polymer.

MeSH terms

  • Acrylic Resins / chemistry*
  • Anti-Infective Agents / pharmacology
  • Biofilms / drug effects*
  • Ciprofloxacin / pharmacology
  • Enterococcus faecalis / drug effects*
  • Enterococcus faecalis / physiology
  • Nitric Oxide / pharmacology*
  • Pseudomonas aeruginosa / drug effects*
  • Pseudomonas aeruginosa / physiology
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / physiology

Substances

  • Acrylic Resins
  • Anti-Infective Agents
  • polyacrylonitrile
  • Nitric Oxide
  • Ciprofloxacin