Antimicrobial Effect of Potassium Iodide Combined with Methylene Blue-Mediated Photodynamic Therapy on Cultured Subgingival Plaque-Derived Polymicrobial Suspensions.
- 1Department of Stomatology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin 150001, China.
- 2Department of Stomatology, Sanya Central Hospital Affiliated to Hainan Medical College, Sanya 572022, China.
- 3Division of Periodontology, Hokkaido University, Sapporo 060-0808, Japan.
Abstract
This study evaluated the antimicrobial efficacy of potassium iodide (KI) combined with methylene blue-mediated photodynamic therapy (MB-PDT) against cultured planktonic polymicrobial suspensions derived from clinical subgingival plaque samples. Bacterial suspensions were assigned to untreated control, light-only, KI-only, MB-PDT, and MB + KI-PDT groups. Neither light irradiation alone nor KI alone significantly affected viable bacterial counts compared with the untreated control. Antibacterial activity was assessed using colony-forming unit (CFU) assays and LIVE/DEAD fluorescence staining, and the virulence-related genes kgp, cdtB, and ltxA were evaluated by RT-qPCR. MB-PDT significantly reduced viable bacterial counts, and the addition of 80 mM KI further enhanced the antibacterial effect. The MB + KI-PDT group showed reductions of approximately 1.89 Log10 CFU/mL compared with the untreated control and 0.45 Log10 CFU/mL compared with MB-PDT alone. LIVE/DEAD staining supported the enhanced antibacterial activity of the combined treatment. The relative transcript levels of kgp, cdtB, and ltxA were also lower after MB + KI-PDT. These findings demonstrate that KI enhanced the antimicrobial activity of MB-PDT in a cultured subgingival plaque-derived planktonic polymicrobial suspension model. Further validation in structured multispecies biofilm models is required.
Related
- Effects of combined basic periodontal treatment and photodynamic therapy on subgingival plaque and inflammatory factors in patients with severe periodontitis.
- Introducing 2-Thioxocoumarins as a New Class of Photosensitizers for Antimicrobial Photodynamic Therapy
- Phthalocyanine photosensitizers in antimicrobial photodynamic therapy as a multifunctional strategy for combating antimicrobial resistance.
- Immediate and residual antimicrobial effects of adjunctive photodynamic therapy on
- Adjunctive Strategies to Enhance Antimicrobial Photodynamic Therapy in Oral Infections: A Systematic Review of Randomized Controlled Trials
BibTeX
@article{gou2026antimicrobial,
title = {{Antimicrobial Effect of Potassium Iodide Combined with Methylene Blue-Mediated Photodynamic Therapy on Cultured Subgingival Plaque-Derived Polymicrobial Suspensions.}},
author = {Yu Gou and Yuan Chen and Liangjia Bi and Chen He and Shengteng He and Deshu Zhuang},
journal = {Pathogens (Basel, Switzerland)},
year = {2026},
month = sep,
doi = {10.3390/pathogens15101031},
url = {https://europepmc.org/article/MED/42931183},
note = {CC BY},
}
RIS
TY - JOUR
TI - Antimicrobial Effect of Potassium Iodide Combined with Methylene Blue-Mediated Photodynamic Therapy on Cultured Subgingival Plaque-Derived Polymicrobial Suspensions.
AU - Yu Gou
AU - Yuan Chen
AU - Liangjia Bi
AU - Chen He
AU - Shengteng He
AU - Deshu Zhuang
PY - 2026
DA - 2026/09/30
JO - Pathogens (Basel, Switzerland)
DO - 10.3390/pathogens15101031
UR - https://europepmc.org/article/MED/42931183
AB - This study evaluated the antimicrobial efficacy of potassium iodide (KI) combined with methylene blue-mediated photodynamic therapy (MB-PDT) against cultured planktonic polymicrobial suspensions derived from clinical subgingival plaque samples. Bacterial suspensions were assigned to untreated control, light-only, KI-only, MB-PDT, and MB + KI-PDT groups. Neither light irradiation alone nor KI alone significantly affected viable bacterial counts compared with the untreated control. Antibacterial activity was assessed using colony-forming unit (CFU) assays and LIVE/DEAD fluorescence staining, and the virulence-related genes kgp, cdtB, and ltxA were evaluated by RT-qPCR. MB-PDT significantly reduced viable bacterial counts, and the addition of 80 mM KI further enhanced the antibacterial effect. The MB + KI-PDT group showed reductions of approximately 1.89 Log10 CFU/mL compared with the untreated control and 0.45 Log10 CFU/mL compared with MB-PDT alone. LIVE/DEAD staining supported the enhanced antibacterial activity of the combined treatment. The relative transcript levels of kgp, cdtB, and ltxA were also lower after MB + KI-PDT. These findings demonstrate that KI enhanced the antimicrobial activity of MB-PDT in a cultured subgingival plaque-derived planktonic polymicrobial suspension model. Further validation in structured multispecies biofilm models is required.
SN - 2076-0817
ER -