Investigation of the antimicrobial effect of anodic iontophoresis on Gram-positive and Gram-negative bacteria for skin infections treatment

• Published in: Bioelectrochemistry (Amsterdam, Netherlands) Netherlands), 2023-06, Vol.151, p.108374-108374, Article 108374
• Main Authors: Gerotto Viola, Sofia, Facco Dalmolin, Luciana, Villarruel Muñoz, Janette Betzabeth, Araújo Martins, Yugo, dos Santos Ré, Ana Carolina, Aires, Carolina Patrícia, Fonseca Vianna Lopez, Renata
• Format: Article
• Language: English
• Subjects: Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Bacteria; Escherichia coli; Gram-Negative Bacteria; Gram-Positive Bacteria; Iontophoresis
• ISSN: 1567-5394; 1878-562X
• DOI: 10.1016/j.bioelechem.2023.108374

[Display omitted] •E. coli is more susceptible to iontophoretic parameter changes than S. epidermidis.•Iontophoresis altered bacteria morphology and induced high rates of E. coli death.•Anodic iontophoresis can control Gram-negative bacterial proliferation in wounds. Iontophoresis, a non-invasive application of a constant low-intensity electric current, is a promising strategy to accelerate wound healing. Although its mechanisms are not yet fully elucidated, part of its action seems related to inhibiting bacteria growth. This work aimed to investigate the antimicrobial effect of iontophoresis using Staphylococcus epidermidis and Escherichia coli strains, Gram-positive and Gram-negative bacteria, respectively. Anodic iontophoresis was applied to each bacterial suspension using Ag/AgCl electrodes, and bacteria viability was evaluated after 24 h incubation by counting colony-forming units. A Quality-by-Design approach was performed to assess the influence of the iontophoresis’ intensity and application time on bacterial viability. Cell morphology was evaluated by scanning electron microscopy. Iontophoresis showed antimicrobial effects on the Gram-positive bacteria only at 5 mA and 60 min application. However, a linear relationship was observed between intensity and application time for the Gram-negative one, causing drastic morphological changes and up to 98 % death. The cell wall of Gram-negative bacteria seems more susceptible to disorganization triggered by iontophoresis-induced ion transport than Gram-positive ones. Therefore, anodic iontophoresis can be a powerful ally in controlling Gram-negative bacteria proliferation in wounds.