Alternating magnetic fields and antibiotics eradicate biofilm on metal in a synergistic fashion

NPJ Biofilms Microbiomes. 2021 Aug 12;7(1):68. doi: 10.1038/s41522-021-00239-y.

Abstract

Hundreds of thousands of human implant procedures require surgical revision each year due to infection. Infections are difficult to treat with conventional antibiotics due to the formation of biofilm on the implant surface. We have developed a noninvasive method to eliminate biofilm on metal implants using heat generated by intermittent alternating magnetic fields (iAMF). Here, we demonstrate that heat and antibiotics are synergistic in biofilm elimination. For Pseudomonas aeruginosa biofilm, bacterial burden was reduced >3 log with iAMF and ciprofloxacin after 24 h compared with either treatment alone (p < 0.0001). This effect was not limited by pathogen or antibiotic as similar biofilm reductions were seen with iAMF and either linezolid or ceftriaxone in Staphylococcus aureus. iAMF and antibiotic efficacy was seen across various iAMF settings, including different iAMF target temperatures, dose durations, and dosing intervals. Initial mechanistic studies revealed membrane disruption as one factor important for AMF enhanced antibacterial activity in the biofilm setting. This study demonstrates the potential of utilizing a noninvasive approach to reduce biofilm off of metallic implants.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Bacteria / drug effects
  • Bacteria / radiation effects
  • Biofilms / drug effects*
  • Biofilms / radiation effects*
  • Ciprofloxacin / pharmacology
  • Drug Resistance, Bacterial
  • Humans
  • Magnetic Fields*
  • Metals*
  • Microbial Sensitivity Tests
  • Prostheses and Implants / microbiology
  • Pseudomonas aeruginosa / drug effects
  • Pseudomonas aeruginosa / radiation effects
  • Staphylococcus aureus / drug effects
  • Staphylococcus aureus / radiation effects

Substances

  • Anti-Bacterial Agents
  • Metals
  • Ciprofloxacin