Antiseptics' Concentration, Combination, and Exposure Time on Bacterial and Fungal Biofilm Eradication

Background: This study aims to assess the activity of solutions containing povidone-iodine (PI) and hydrogen peroxide (H2O2) alone or combined on the biofilm of microbial species in the contest of periprosthetic joint infection (PJI). Methods: Different antiseptic solutions were tested on 2-day-old biofilms of Gram-positive and Gramnegative bacteria and fungi at 1 and 3 minutes of exposure. The efficacy of these solutions was evaluated by measuring the biofilm metabolic activity by methoxynitrosulfophenyl-tetrazolium carboxanilide (XTT) reduction assay. The anti-biofilm effect of 5% PI and 0.3% PI + 0.5% H2O2 was tested on a 5-day-old biofilm using colony-forming unit counts and an XTT reduction assay. Results: PI and H2O2 solutions showed concentration-dependent anti-biofilm activity except for E. faecalis. PI at 5% was the most active solution against the 2-day-old biofilm of all test microorganisms. The 0.3% PI + 0.5% H zO z solution had a significant effect only at 3 minutes. The 5% PI and 0.3% PI + 0.5% H zO z effect was evaluated on 5-day-old biofilms. PI at 5% produced a significant reduction in metabolic activity at both 1 and 3 minutes; 0.3% PI + 0.5% H zO z caused a significant activity against all Grampositive strains after 3 minutes, with a greater metabolic activity reduction than 5% PI. Conclusions: In the case of PJI caused by Gram-positive bacteria, 0.3% PI + 0.5% H zO z could be used for wound irrigation for 3 minutes of exposure. In the case of PJI with a different etiological agent or PJI with an unknown etiology, it is advisable to use 5% PI for 1 minute of exposure. (c) 2024 The Authors. Published by Elsevier Inc. on behalf of The American Association of Hip and Knee Surgeons. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/ 4.0/).