Quantitative Determination of Dark and Light-Activated Antimicrobial Activity of Poly(Phenylene Ethynylene), Polythiophene, and Oligo(Phenylene Ethynylene) Electrolytes

ACS Appl Mater Interfaces. 2020 May 13;12(19):21322-21329. doi: 10.1021/acsami.0c02939. Epub 2020 Apr 7.


Much recent effort has been directed toward the development of novel antimicrobial materials able to defeat new and antibiotic resistant pathogens. In this report, we study the efficacy of cationic poly(phenylene ethynylene), polythiophene, and oligo(phenylene ethynylene) electrolytes against laboratory strains of Pseudomonas aeruginosa, Staphylococcus aureus and Staphylococcus epidermidis. The focus of the study is to quantitatively evaluate the speed and extent of dark and light-activated antimicrobial activity. Using cell plating with serial dilutions, we determined that planktonic bacteria suspensions exposed to the antimicrobials (at 10 μg/mL) result in several log kills at 10 min both in the dark and under UV irradiation (360 nm) for all eight synthetic antimicrobials. However, there are significant differences in the ease of killing the different pathogens. In most trials, there is significantly greater killing under light-irradiation, indicating these materials may be used as versatile disinfectants.

Keywords: Pseudomonas aeruginosa; Staphylococcus aureus; antimicrobial polyelectrolytes; conjugated polyelectrolytes; oligomeric electrolytes; poly(phenylene)-ethynylene polyelectrolytes; poly-3-hexyl-thiophene polyelectrolytes.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / radiation effects
  • Darkness
  • Disinfectants / pharmacology*
  • Disinfectants / radiation effects
  • Microbial Sensitivity Tests
  • Polymers / pharmacology*
  • Polymers / radiation effects
  • Pseudomonas aeruginosa / drug effects
  • Staphylococcus aureus / drug effects
  • Staphylococcus epidermidis / drug effects
  • Thiophenes / pharmacology*
  • Thiophenes / radiation effects
  • Ultraviolet Rays


  • Anti-Bacterial Agents
  • Disinfectants
  • Polymers
  • Thiophenes
  • poly(phenylene ethynylene)
  • polythiophene