Electrically-responsive antimicrobial coatings based on a tetracycline-loaded poly(3,4-ethylenedioxythiophene) matrix

Mater Sci Eng C Mater Biol Appl. 2021 Apr:123:112017. doi: 10.1016/j.msec.2021.112017. Epub 2021 Mar 9.

Abstract

The growth of bacteria and the formation of complex bacterial structures on biomedical devices is a major challenge in modern medicine. The aim of this study was to develop a biocompatible, conducting and antibacterial polymer coating applicable in biomedical engineering. Since conjugated polymers have recently aroused strong interest as controlled delivery systems for biologically active compounds, we decided to employ a poly(3,4-ethylenedioxythiophene) (PEDOT) matrix to immobilize a powerful, first-line antibiotic: tetracycline (Tc). Drug immobilization was carried out simultaneously with the electrochemical polymerization process, allowing to obtain a polymer coating with good electrochemical behaviour (charge storage capacity of 19.15 ± 6.09 mC/cm2) and high drug loading capacity (194.7 ± 56.2 μg/cm2). Biological activity of PEDOT/Tc matrix was compared with PEDOT matrix and a bare Pt surface against a model Gram-negative bacteria strain of Escherichia coli with the use of LIVE/DEAD assay and SEM microscopy. Finally, PEDOT/Tc was shown to serve as a robust electroactive coating exhibiting antibacterial activity.

Keywords: Antimicrobial activity; Bacterial growth; Conjugated polymers; Escherichia coli; Poly(3,4-ethylenedioxythiophene); Tetracycline.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Anti-Infective Agents*
  • Bridged Bicyclo Compounds, Heterocyclic / pharmacology
  • Polymers*

Substances

  • Anti-Bacterial Agents
  • Anti-Infective Agents
  • Bridged Bicyclo Compounds, Heterocyclic
  • Polymers
  • poly(3,4-ethylene dioxythiophene)